diff --git a/plugins/alarm/alarm_node.cpp b/plugins/alarm/alarm_node.cpp
index aa55853..e93a527 100644
--- a/plugins/alarm/alarm_node.cpp
+++ b/plugins/alarm/alarm_node.cpp
@@ -951,7 +951,8 @@ private:
 
                 Detection d;
                 d.cls_id = -1;
-                d.score = it.best_sim;
+                // Unknown: show stranger likelihood (1 - best_sim). Known: show match confidence (best_sim).
+                d.score = (rule.kind == FaceRule::Kind::Unknown) ? (1.0f - it.best_sim) : it.best_sim;
                 d.bbox = it.bbox;
                 d.track_id = it.person_track_id >= 0 ? it.person_track_id : it.best_person_id;
                 dets.push_back(std::move(d));