diff --git a/src/main/kotlin/com/project/movienight/adapters/jellyfin/JellyfinApiClient.kt b/src/main/kotlin/com/project/movienight/adapters/jellyfin/JellyfinApiClient.kt
new file mode 100644
index 0000000..a21d103
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/adapters/jellyfin/JellyfinApiClient.kt
@@ -0,0 +1,143 @@
+package com.project.movienight.adapters.jellyfin
+
+import com.fasterxml.jackson.databind.JsonNode
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.project.movienight.config.JellyfinIntegrationProperties
+import com.project.movienight.domain.model.ContentType
+import org.springframework.stereotype.Service
+import java.net.URI
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpResponse
+import java.time.Duration
+
+data class JellyfinRemoteUser(
+    val id: String,
+    val name: String,
+)
+
+data class JellyfinLibraryItemSnapshot(
+    val jellyfinItemId: String,
+    val title: String,
+    val description: String,
+    val contentType: ContentType,
+    val releaseYear: Int?,
+    val genres: List<String>,
+    val cast: List<String>,
+    val directors: List<String>,
+    val platformRating: Double?,
+    val imdbRating: Double?,
+    val externalUrl: String?,
+    val jellyfinLibraryId: String?,
+    val isPlayed: Boolean,
+)
+
+@Service
+class JellyfinApiClient(
+    private val properties: JellyfinIntegrationProperties,
+    private val objectMapper: ObjectMapper,
+) {
+    private val httpClient: HttpClient =
+        HttpClient
+            .newBuilder()
+            .connectTimeout(Duration.ofMillis(properties.requestTimeoutMs))
+            .build()
+
+    fun fetchUsers(): List<JellyfinRemoteUser> =
+        request("Users")
+            .asItems()
+            .mapNotNull { node ->
+                val id = node.fieldText("Id") ?: return@mapNotNull null
+                JellyfinRemoteUser(id = id, name = node.fieldText("Name") ?: id)
+            }
+
+    fun fetchLibraryItems(userId: String): List<JellyfinLibraryItemSnapshot> =
+        @Suppress("MaxLineLength")
+        request(
+            "Users/$userId/Items?Recursive=true&IncludeItemTypes=Movie,Series,Episode&Fields=Genres,People,ProviderIds,Overview,ProductionYear,CommunityRating,OfficialRating,ParentId,UserData",
+        ).asItems().mapNotNull { node ->
+            val itemId = node.fieldText("Id") ?: return@mapNotNull null
+            val providerIds = node["ProviderIds"]
+            val imdbId = providerIds?.fieldText("Imdb")
+            val people = node["People"]
+            val cast = people?.peopleByType("Actor", "GuestStar") ?: emptyList()
+            val directors = people?.peopleByType("Director") ?: emptyList()
+            JellyfinLibraryItemSnapshot(
+                jellyfinItemId = itemId,
+                title = node.fieldText("Name") ?: itemId,
+                description = node.fieldText("Overview") ?: "",
+                contentType = mapContentType(node.fieldText("Type")),
+                releaseYear = node["ProductionYear"]?.takeUnless { it.isNull }?.asInt(),
+                genres = node["Genres"]?.textList() ?: emptyList(),
+                cast = cast,
+                directors = directors,
+                platformRating = node["CommunityRating"]?.takeUnless { it.isNull }?.asDouble(),
+                imdbRating = null,
+                externalUrl = imdbId?.let { "https://www.imdb.com/title/$it/" },
+                jellyfinLibraryId = node.fieldText("ParentId"),
+                isPlayed =
+                    node["UserData"]?.booleanField("Played") ?: node["UserData"]?.booleanField("IsPlayed") ?: false,
+            )
+        }
+
+    private fun request(path: String): JsonNode {
+        val uri = URI.create("${properties.baseUrl.trimEnd('/')}/$path")
+        val request =
+            HttpRequest
+                .newBuilder(uri)
+                .timeout(Duration.ofMillis(properties.requestTimeoutMs))
+                .header("Accept", "application/json")
+                .header("X-Emby-Token", properties.apiKey)
+                .GET()
+                .build()
+
+        val response =
+            try {
+                httpClient.send(request, HttpResponse.BodyHandlers.ofString())
+            } catch (
+                @Suppress("TooGenericExceptionCaught") exception: Exception,
+            ) {
+                throw IllegalStateException("Failed to call Jellyfin at $uri", exception)
+            }
+
+        check(response.statusCode() !in 200..299) {
+            "Jellyfin request failed with status ${response.statusCode()} for $uri"
+        }
+
+        return objectMapper.readTree(response.body())
+    }
+
+    private fun JsonNode.asItems(): List<JsonNode> =
+        when {
+            isArray -> map { it }
+            has("Items") && this["Items"].isArray -> this["Items"].map { it }
+            else -> emptyList()
+        }
+
+    private fun JsonNode.fieldText(name: String): String? =
+        get(name)?.takeUnless { it.isNull }?.asText()?.takeIf { it.isNotBlank() }
+
+    private fun JsonNode.booleanField(name: String): Boolean? = get(name)?.takeUnless { it.isNull }?.asBoolean()
+
+    private fun JsonNode.textList(): List<String> =
+        takeIf { it.isArray }?.mapNotNull { item ->
+            item.takeUnless { it.isNull }?.asText()?.takeIf { text -> text.isNotBlank() }
+        }
+            ?: emptyList()
+
+    private fun JsonNode.peopleByType(vararg types: String): List<String> {
+        if (!isArray) return emptyList()
+        return mapNotNull { person ->
+            val type = person.fieldText("Type") ?: return@mapNotNull null
+            if (types.any { it.equals(type, ignoreCase = true) }) person.fieldText("Name") else null
+        }
+    }
+
+    private fun mapContentType(value: String?): ContentType =
+        when (value?.lowercase()) {
+            "movie" -> ContentType.FILM
+            "series" -> ContentType.SERIES
+            "episode" -> ContentType.EPISODE
+            else -> ContentType.OTHER
+        }
+}
diff --git a/src/main/kotlin/com/project/movienight/adapters/web/JellyfinEventsController.kt b/src/main/kotlin/com/project/movienight/adapters/web/JellyfinEventsController.kt
new file mode 100644
index 0000000..3708530
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/adapters/web/JellyfinEventsController.kt
@@ -0,0 +1,52 @@
+package com.project.movienight.adapters.web
+
+import com.project.movienight.adapters.web.dto.request.JellyfinEventRequest
+import com.project.movienight.application.services.JellyfinEventService
+import com.project.movienight.config.JellyfinIntegrationProperties
+import org.slf4j.LoggerFactory
+import org.springframework.http.HttpStatus
+import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.RequestBody
+import org.springframework.web.bind.annotation.RequestHeader
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.ResponseStatus
+import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.server.ResponseStatusException
+
+@RestController
+@RequestMapping("/api/integrations/jellyfin")
+class JellyfinEventsController(
+    private val jellyfinEventService: JellyfinEventService,
+    private val properties: JellyfinIntegrationProperties,
+) {
+    private val log = LoggerFactory.getLogger(JellyfinEventsController::class.java)
+
+    @PostMapping("/events")
+    @ResponseStatus(HttpStatus.OK)
+    fun receiveEvent(
+        @RequestHeader(value = "X-MovieNight-Plugin-Token", required = false) token: String?,
+        @RequestBody request: JellyfinEventRequest,
+    ) {
+        if (properties.pluginToken.isNotBlank()) {
+            if (token == null || token != properties.pluginToken) {
+                throw ResponseStatusException(HttpStatus.UNAUTHORIZED, "Invalid plugin token")
+            }
+        }
+
+        log.debug(
+            "Received Jellyfin event {} for user {} item {}",
+            request.eventId,
+            request.jellyfinUserId,
+            request.itemId,
+        )
+        jellyfinEventService.handleEvent(
+            eventId = request.eventId,
+            serverId = null,
+            eventType = request.eventType,
+            occurredAt = request.occurredAt,
+            jellyfinUserId = request.jellyfinUserId,
+            itemId = request.itemId,
+            payload = request.payload,
+        )
+    }
+}
diff --git a/src/main/kotlin/com/project/movienight/adapters/web/JellyfinSyncController.kt b/src/main/kotlin/com/project/movienight/adapters/web/JellyfinSyncController.kt
new file mode 100644
index 0000000..74aac90
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/adapters/web/JellyfinSyncController.kt
@@ -0,0 +1,21 @@
+package com.project.movienight.adapters.web
+
+import com.project.movienight.application.services.JellyfinSyncService
+import com.project.movienight.domain.model.JellyfinSyncState
+import com.project.movienight.domain.model.JellyfinSyncSummary
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RestController
+
+@RestController
+@RequestMapping("/api/integrations/jellyfin")
+class JellyfinSyncController(
+    private val jellyfinSyncService: JellyfinSyncService,
+) {
+    @PostMapping("/sync")
+    fun syncNow(): JellyfinSyncSummary = jellyfinSyncService.syncNow()
+
+    @GetMapping("/sync-state")
+    fun syncState(): List<JellyfinSyncState> = jellyfinSyncService.getSyncStates()
+}
diff --git a/src/main/kotlin/com/project/movienight/adapters/web/dto/request/JellyfinEventRequest.kt b/src/main/kotlin/com/project/movienight/adapters/web/dto/request/JellyfinEventRequest.kt
new file mode 100644
index 0000000..68abfe8
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/adapters/web/dto/request/JellyfinEventRequest.kt
@@ -0,0 +1,21 @@
+package com.project.movienight.adapters.web.dto.request
+
+import com.fasterxml.jackson.annotation.JsonProperty
+import java.time.OffsetDateTime
+
+data class JellyfinEventRequest(
+    @JsonProperty("event_id")
+    val eventId: String,
+    @JsonProperty("event_type")
+    val eventType: String,
+    @JsonProperty("occurred_at")
+    val occurredAt: OffsetDateTime,
+    @JsonProperty("jellyfin_user_id")
+    val jellyfinUserId: String,
+    @JsonProperty("item_id")
+    val itemId: String,
+    @JsonProperty("payload_version")
+    val payloadVersion: Int = 1,
+    @JsonProperty("payload")
+    val payload: Map<String, Any>? = null,
+)
diff --git a/src/main/kotlin/com/project/movienight/application/services/JellyfinEventService.kt b/src/main/kotlin/com/project/movienight/application/services/JellyfinEventService.kt
new file mode 100644
index 0000000..8ff3f6b
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/application/services/JellyfinEventService.kt
@@ -0,0 +1,70 @@
+package com.project.movienight.application.services
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.project.movienight.adapters.metrics.BusinessMetricsService
+import com.project.movienight.adapters.persistence.jdbc.JellyfinEventRepository
+import com.project.movienight.application.ports.input.MarkFilmViewedCommand
+import com.project.movienight.application.ports.input.MarkFilmViewedUseCase
+import com.project.movienight.application.ports.output.FilmRepositoryPort
+import com.project.movienight.application.ports.output.UserRepositoryPort
+import org.springframework.stereotype.Service
+import java.time.OffsetDateTime
+
+@Service
+class JellyfinEventService(
+    private val jellyfinEventRepository: JellyfinEventRepository,
+    private val userRepository: UserRepositoryPort,
+    private val filmRepository: FilmRepositoryPort,
+    private val markFilmViewedUseCase: MarkFilmViewedUseCase,
+    private val objectMapper: ObjectMapper,
+    private val businessMetricsService: BusinessMetricsService,
+) {
+    private val playbackEventTypes = setOf("playback.ended", "playback.stopped", "playback.completed")
+
+    fun handleEvent(
+        eventId: String,
+        serverId: String?,
+        eventType: String,
+        occurredAt: OffsetDateTime,
+        jellyfinUserId: String,
+        itemId: String,
+        payload: Map<String, Any>?,
+    ) {
+        if (jellyfinEventRepository.exists(eventId = eventId)) {
+            return
+        }
+
+        val payloadJson = payload?.let { objectMapper.writeValueAsString(it) }
+        jellyfinEventRepository.save(eventId, serverId, eventType, occurredAt, jellyfinUserId, itemId, payloadJson)
+
+        try {
+            if (playbackEventTypes.contains(eventType)) {
+                val localUser = userRepository.findAll().firstOrNull { it.jellyfinUserId == jellyfinUserId }
+                if (localUser == null) {
+                    businessMetricsService.recordJellyfinUnmappedUser()
+                    return
+                }
+
+                val film = filmRepository.findByJellyfinItemId(itemId)
+                if (film == null) {
+                    businessMetricsService.recordBackendWriteFailure()
+                    return
+                }
+
+                markFilmViewedUseCase.markViewed(
+                    MarkFilmViewedCommand(
+                        userId = localUser.id,
+                        filmId = film.id,
+                        watchedAt = occurredAt.toLocalDateTime(),
+                    ),
+                )
+                businessMetricsService.recordLibraryEvent()
+            }
+        } catch (
+            @Suppress("TooGenericExceptionCaught") ex: RuntimeException,
+        ) {
+            businessMetricsService.recordBackendWriteFailure()
+            throw ex
+        }
+    }
+}
diff --git a/src/main/kotlin/com/project/movienight/application/services/JellyfinSyncService.kt b/src/main/kotlin/com/project/movienight/application/services/JellyfinSyncService.kt
new file mode 100644
index 0000000..46faa88
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/application/services/JellyfinSyncService.kt
@@ -0,0 +1,153 @@
+package com.project.movienight.application.services
+
+import com.project.movienight.adapters.jellyfin.JellyfinApiClient
+import com.project.movienight.adapters.jellyfin.JellyfinLibraryItemSnapshot
+import com.project.movienight.adapters.jellyfin.JellyfinRemoteUser
+import com.project.movienight.adapters.metrics.BusinessMetricsService
+import com.project.movienight.application.ports.output.FilmLibraryRepositoryPort
+import com.project.movienight.application.ports.output.FilmRepositoryPort
+import com.project.movienight.application.ports.output.IdGenerator
+import com.project.movienight.application.ports.output.JellyfinSyncStateRepositoryPort
+import com.project.movienight.application.ports.output.UserRepositoryPort
+import com.project.movienight.config.JellyfinIntegrationProperties
+import com.project.movienight.domain.model.ContentType
+import com.project.movienight.domain.model.Film
+import com.project.movienight.domain.model.FilmLibrary
+import com.project.movienight.domain.model.JellyfinSyncState
+import com.project.movienight.domain.model.JellyfinSyncSummary
+import org.springframework.scheduling.annotation.Scheduled
+import org.springframework.stereotype.Service
+import java.time.Duration
+import java.time.Instant
+import java.time.LocalDateTime
+
+@Service
+class JellyfinSyncService(
+    private val properties: JellyfinIntegrationProperties,
+    private val jellyfinApiClient: JellyfinApiClient,
+    private val userRepository: UserRepositoryPort,
+    private val filmRepository: FilmRepositoryPort,
+    private val filmLibraryRepository: FilmLibraryRepositoryPort,
+    private val syncStateRepository: JellyfinSyncStateRepositoryPort,
+    private val idGenerator: IdGenerator,
+    private val businessMetricsService: BusinessMetricsService,
+) {
+    @Scheduled(fixedDelayString = "\${integrations.jellyfin.sync-interval-ms:1800000}")
+    fun scheduledSync() {
+        if (properties.enabled) {
+            syncNow()
+        }
+    }
+
+    fun syncNow(): JellyfinSyncSummary {
+        if (!properties.enabled || properties.baseUrl.isBlank() || properties.apiKey.isBlank()) {
+            return JellyfinSyncSummary(syncedUsers = 0, skippedUsers = 0, syncedItems = 0, durationMs = 0)
+        }
+
+        val startedAt = Instant.now()
+        val remoteUsers = jellyfinApiClient.fetchUsers()
+        val localUsersByJellyfinId =
+            userRepository
+                .findAll()
+                .mapNotNull { user ->
+                    user.jellyfinUserId?.let { it to user }
+                }.toMap()
+
+        var syncedUsers = 0
+        var skippedUsers = 0
+        var syncedItems = 0
+
+        remoteUsers.forEach { remoteUser ->
+            val localUser = localUsersByJellyfinId[remoteUser.id]
+            if (localUser == null) {
+                skippedUsers += 1
+                return@forEach
+            }
+
+            val items = jellyfinApiClient.fetchLibraryItems(remoteUser.id)
+            items.forEach { item ->
+                syncItem(localUser.id, item)
+                syncedItems += 1
+            }
+
+            val now = LocalDateTime.now()
+            syncStateRepository.save(
+                JellyfinSyncState(
+                    userId = localUser.id,
+                    lastSyncedAt = now,
+                    lastSuccessfulSyncAt = now,
+                    lastError = null,
+                    syncedItemCount = items.size,
+                ),
+            )
+            syncedUsers += 1
+        }
+
+        val summary =
+            JellyfinSyncSummary(
+                syncedUsers = syncedUsers,
+                skippedUsers = skippedUsers,
+                syncedItems = syncedItems,
+                durationMs = Duration.between(startedAt, Instant.now()).toMillis(),
+            )
+        businessMetricsService.recordJellyfinSync(summary)
+        return summary
+    }
+
+    fun getSyncStates(): List<JellyfinSyncState> = syncStateRepository.findAll()
+
+    private fun syncItem(
+        userId: java.util.UUID,
+        item: JellyfinLibraryItemSnapshot,
+    ) {
+        val film =
+            filmRepository.findByJellyfinItemId(item.jellyfinItemId)?.copy(
+                title = item.title,
+                description = item.description,
+                contentType = item.contentType,
+                releaseYear = item.releaseYear,
+                genres = item.genres,
+                cast = item.cast,
+                directors = item.directors,
+                imdbRating = item.imdbRating,
+                platformRating = item.platformRating,
+                externalUrl = item.externalUrl,
+                jellyfinItemId = item.jellyfinItemId,
+                jellyfinLibraryId = item.jellyfinLibraryId,
+            ) ?: Film(
+                id = idGenerator.generateId(),
+                title = item.title,
+                description = item.description,
+                contentType = item.contentType,
+                releaseYear = item.releaseYear,
+                genres = item.genres,
+                cast = item.cast,
+                directors = item.directors,
+                imdbRating = item.imdbRating,
+                platformRating = item.platformRating,
+                externalUrl = item.externalUrl,
+                jellyfinItemId = item.jellyfinItemId,
+                jellyfinLibraryId = item.jellyfinLibraryId,
+            )
+
+        val savedFilm = filmRepository.save(film)
+
+        if (item.isPlayed) {
+            val watchedAt = LocalDateTime.now()
+            val existingEntry = filmLibraryRepository.findByUserIdAndFilmId(userId, savedFilm.id)
+            filmLibraryRepository.save(
+                existingEntry?.copy(
+                    isViewed = true,
+                    watchedAt = watchedAt,
+                ) ?: FilmLibrary(
+                    id = idGenerator.generateId(),
+                    userId = userId,
+                    filmId = savedFilm.id,
+                    comment = null,
+                    isViewed = true,
+                    watchedAt = watchedAt,
+                ),
+            )
+        }
+    }
+}
diff --git a/src/main/kotlin/com/project/movienight/config/JellyfinIntegrationProperties.kt b/src/main/kotlin/com/project/movienight/config/JellyfinIntegrationProperties.kt
new file mode 100644
index 0000000..5a59400
--- /dev/null
+++ b/src/main/kotlin/com/project/movienight/config/JellyfinIntegrationProperties.kt
@@ -0,0 +1,13 @@
+package com.project.movienight.config
+
+import org.springframework.boot.context.properties.ConfigurationProperties
+
+@ConfigurationProperties(prefix = "integrations.jellyfin")
+data class JellyfinIntegrationProperties(
+    val enabled: Boolean = false,
+    val baseUrl: String = "",
+    val apiKey: String = "",
+    val syncIntervalMs: Long = 1_800_000,
+    val requestTimeoutMs: Long = 20_000,
+    val pluginToken: String = "",
+)
diff --git a/src/main/resources/db/migration/V2__jellyfin_events.sql b/src/main/resources/db/migration/V3__jellyfin_events.sql
similarity index 100%
rename from src/main/resources/db/migration/V2__jellyfin_events.sql
rename to src/main/resources/db/migration/V3__jellyfin_events.sql