diff --git a/src/bus.rs b/src/bus.rs
index 97a7307..f0a6e57 100644
--- a/src/bus.rs
+++ b/src/bus.rs
@@ -183,6 +183,11 @@ impl Listener for CampaignListener {
     fn turn_start(&mut self, input: &str, speaker: Speaker) {
         self.input = input.to_string();
         self.speaker = speaker;
+        // Clear last turn's narration. `delta` appends to this all turn
+        // long, and `done` writes it whole, so without the reset every
+        // turn would replay every earlier turn's narration into the
+        // transcript, growing it unboundedly.
+        self.narration.clear();
     }
 
     fn delta(&mut self, text: &str) -> Flow {
diff --git a/src/bus_tests.rs b/src/bus_tests.rs
index 2ab2307..c87a857 100644
--- a/src/bus_tests.rs
+++ b/src/bus_tests.rs
@@ -363,3 +363,36 @@ fn default_listener_methods_do_not_panic() {
     bus.cancelled("partial");
     bus.failed("error");
 }
+
+#[test]
+fn campaign_listener_does_not_replay_earlier_turns_narration() {
+    use crate::campaign::Campaign;
+    use crate::campaign::GameTime;
+
+    let dir = tempfile::TempDir::new().unwrap();
+    let campaign = Campaign::open(dir.path()).unwrap();
+    let mut bus = TurnBus::new();
+    bus.add(Box::new(CampaignListener::new(Some(campaign))));
+
+    // First turn.
+    bus.turn_start("I wake up.", Speaker::Player);
+    let _ = bus.delta("You wake in a cold cell.");
+    bus.done("You wake in a cold cell.");
+
+    // Second turn, later that day. Without the reset in turn_start, this
+    // would re-append the first turn's narration before its own.
+    let campaign = Campaign::open(dir.path()).unwrap();
+    campaign
+        .mark(GameTime::parse("#d1-0900").unwrap(), "time passes", None)
+        .unwrap();
+    bus.turn_start("I sit up.", Speaker::Player);
+    let _ = bus.delta("The bars are iron.");
+    bus.done("The bars are iron.");
+
+    let campaign = Campaign::open(dir.path()).unwrap();
+    let sections = campaign.transcript_entries().unwrap();
+    let bodies: Vec<String> = sections.into_iter().map(|e| e.body).collect();
+    assert_eq!(bodies.len(), 2);
+    assert_eq!(bodies[0], "player> I wake up.\n\nYou wake in a cold cell.");
+    assert_eq!(bodies[1], "player> I sit up.\n\nThe bars are iron.");
+}