diff --git a/app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapper.kt b/app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapper.kt
new file mode 100644
index 0000000..c07f44e
--- /dev/null
+++ b/app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapper.kt
@@ -0,0 +1,68 @@
+package de.jeanlucmakiola.calendula.data.calendar
+
+import android.provider.CalendarContract
+import android.util.Log
+import de.jeanlucmakiola.calendula.domain.Attendee
+import de.jeanlucmakiola.calendula.domain.AttendeeStatus
+import de.jeanlucmakiola.calendula.domain.EventDetail
+import de.jeanlucmakiola.calendula.domain.EventInstance
+
+private const val TAG = "EventDetailMapper"
+
+internal fun ColumnReader.toEventDetailCore(attendees: List<Attendee>): EventDetail? {
+    val begin = getLong(EventDetailProjection.IDX_DTSTART)
+    val end = getLong(EventDetailProjection.IDX_DTEND)
+
+    if (begin < 0L) {
+        Log.w(TAG, "Dropping event with negative dtstart=$begin")
+        return null
+    }
+    if (end < begin) {
+        Log.w(TAG, "Dropping event with dtend=$end < dtstart=$begin")
+        return null
+    }
+
+    val rawTitle = getString(EventDetailProjection.IDX_TITLE)
+    val title = if (rawTitle.isNullOrEmpty()) Fallbacks.UNTITLED_EVENT else rawTitle
+
+    val color = if (isNull(EventDetailProjection.IDX_EVENT_COLOR)) {
+        getInt(EventDetailProjection.IDX_CALENDAR_COLOR)
+    } else {
+        getInt(EventDetailProjection.IDX_EVENT_COLOR)
+    }
+
+    val eventId = getLong(EventDetailProjection.IDX_EVENT_ID)
+    val instance = EventInstance(
+        instanceId = eventId,
+        eventId = eventId,
+        calendarId = getLong(EventDetailProjection.IDX_CALENDAR_ID),
+        title = title,
+        start = begin.toKotlinInstantFromEpochMillis(),
+        end = end.toKotlinInstantFromEpochMillis(),
+        isAllDay = getInt(EventDetailProjection.IDX_ALL_DAY) != 0,
+        color = color,
+        location = getString(EventDetailProjection.IDX_LOCATION),
+    )
+
+    return EventDetail(
+        instance = instance,
+        description = getString(EventDetailProjection.IDX_DESCRIPTION),
+        organizer = getString(EventDetailProjection.IDX_ORGANIZER),
+        attendees = attendees,
+        rrule = getString(EventDetailProjection.IDX_RRULE),
+    )
+}
+
+internal fun ColumnReader.toAttendee(): Attendee = Attendee(
+    name = getString(AttendeeProjection.IDX_NAME).orEmpty(),
+    email = getString(AttendeeProjection.IDX_EMAIL),
+    status = mapAttendeeStatus(getInt(AttendeeProjection.IDX_STATUS)),
+)
+
+internal fun mapAttendeeStatus(raw: Int): AttendeeStatus = when (raw) {
+    CalendarContract.Attendees.ATTENDEE_STATUS_ACCEPTED -> AttendeeStatus.Accepted
+    CalendarContract.Attendees.ATTENDEE_STATUS_DECLINED -> AttendeeStatus.Declined
+    CalendarContract.Attendees.ATTENDEE_STATUS_TENTATIVE -> AttendeeStatus.Tentative
+    CalendarContract.Attendees.ATTENDEE_STATUS_INVITED -> AttendeeStatus.NeedsAction
+    else -> AttendeeStatus.Unknown
+}
diff --git a/app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapperTest.kt b/app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapperTest.kt
new file mode 100644
index 0000000..9100767
--- /dev/null
+++ b/app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/EventDetailMapperTest.kt
@@ -0,0 +1,107 @@
+package de.jeanlucmakiola.calendula.data.calendar
+
+import com.google.common.truth.Truth.assertThat
+import de.jeanlucmakiola.calendula.domain.AttendeeStatus
+import org.junit.jupiter.api.Test
+
+class EventDetailMapperTest {
+
+    private fun detailReader(
+        eventId: Long = 1L,
+        title: String? = "Meet",
+        description: String? = "Body",
+        organizer: String? = "x@y",
+        rrule: String? = null,
+        eventColor: Any? = null,
+        calendarColor: Int = 0xFFAABBCC.toInt(),
+        dtstart: Long = 1_000_000_000L,
+        dtend: Long = 1_000_003_600L,
+        allDay: Int = 0,
+        location: String? = "Berlin",
+        calendarId: Long = 7L,
+    ): MapColumnReader = MapColumnReader(
+        EventDetailProjection.IDX_EVENT_ID to eventId,
+        EventDetailProjection.IDX_TITLE to title,
+        EventDetailProjection.IDX_DESCRIPTION to description,
+        EventDetailProjection.IDX_ORGANIZER to organizer,
+        EventDetailProjection.IDX_RRULE to rrule,
+        EventDetailProjection.IDX_EVENT_COLOR to eventColor,
+        EventDetailProjection.IDX_CALENDAR_COLOR to calendarColor,
+        EventDetailProjection.IDX_DTSTART to dtstart,
+        EventDetailProjection.IDX_DTEND to dtend,
+        EventDetailProjection.IDX_ALL_DAY to allDay,
+        EventDetailProjection.IDX_LOCATION to location,
+        EventDetailProjection.IDX_CALENDAR_ID to calendarId,
+    )
+
+    private fun attendeeReader(name: String?, email: String?, status: Int): MapColumnReader =
+        MapColumnReader(
+            AttendeeProjection.IDX_NAME to name,
+            AttendeeProjection.IDX_EMAIL to email,
+            AttendeeProjection.IDX_STATUS to status,
+        )
+
+    @Test
+    fun `happy path detail maps all fields and embeds matching EventInstance`() {
+        val detail = detailReader().toEventDetailCore(attendees = emptyList())
+        assertThat(detail).isNotNull()
+        assertThat(detail!!.description).isEqualTo("Body")
+        assertThat(detail.organizer).isEqualTo("x@y")
+        assertThat(detail.instance.title).isEqualTo("Meet")
+        assertThat(detail.instance.location).isEqualTo("Berlin")
+        assertThat(detail.attendees).isEmpty()
+    }
+
+    @Test
+    fun `event color falls back to calendar color when null`() {
+        val detail = detailReader(eventColor = null, calendarColor = 0xFF112233.toInt())
+            .toEventDetailCore(attendees = emptyList())
+        assertThat(detail!!.instance.color).isEqualTo(0xFF112233.toInt())
+    }
+
+    @Test
+    fun `dtend before dtstart drops detail`() {
+        val detail = detailReader(dtstart = 2000L, dtend = 1000L)
+            .toEventDetailCore(attendees = emptyList())
+        assertThat(detail).isNull()
+    }
+
+    @Test
+    fun `rrule passes through when present`() {
+        val detail = detailReader(rrule = "FREQ=WEEKLY;BYDAY=MO")
+            .toEventDetailCore(attendees = emptyList())
+        assertThat(detail!!.rrule).isEqualTo("FREQ=WEEKLY;BYDAY=MO")
+    }
+
+    // Raw CalendarContract.Attendees status integer constants from the Android
+    // source (kept inline so the test doesn't depend on the mockable.jar's
+    // possibly-stubbed constants):
+    // ACCEPTED=1, DECLINED=2, INVITED=3, TENTATIVE=4, NONE=0
+    @Test
+    fun `attendee status maps known integer codes`() {
+        assertThat(attendeeReader("A", "a@x", 1).toAttendee().status)
+            .isEqualTo(AttendeeStatus.Accepted)
+        assertThat(attendeeReader("B", "b@x", 2).toAttendee().status)
+            .isEqualTo(AttendeeStatus.Declined)
+        assertThat(attendeeReader("C", "c@x", 4).toAttendee().status)
+            .isEqualTo(AttendeeStatus.Tentative)
+        assertThat(attendeeReader("D", "d@x", 3).toAttendee().status)
+            .isEqualTo(AttendeeStatus.NeedsAction)
+        assertThat(attendeeReader("E", "e@x", 0).toAttendee().status)
+            .isEqualTo(AttendeeStatus.Unknown)
+        assertThat(attendeeReader("F", "f@x", 99).toAttendee().status)
+            .isEqualTo(AttendeeStatus.Unknown)
+    }
+
+    @Test
+    fun `attendee with null name maps to empty string`() {
+        val a = attendeeReader(null, "alice@x", 1).toAttendee()
+        assertThat(a.name).isEqualTo("")
+    }
+
+    @Test
+    fun `attendee email passes through nullably`() {
+        assertThat(attendeeReader("A", null, 1).toAttendee().email).isNull()
+        assertThat(attendeeReader("A", "x@y", 1).toAttendee().email).isEqualTo("x@y")
+    }
+}