diff --git a/image_analysis/RotationIndexer.cpp b/image_analysis/RotationIndexer.cpp
index f1c9794d..9743a42c 100644
--- a/image_analysis/RotationIndexer.cpp
+++ b/image_analysis/RotationIndexer.cpp
@@ -146,6 +146,8 @@ std::optional<RotationIndexerResult> RotationIndexer::ProcessImage(int64_t image
 std::optional<RotationIndexerResult> RotationIndexer::Finalize(bool retry) {
     if (!indexed_lattice || retry)
         TryIndex();
+    if (!indexed_lattice)
+        return std::nullopt;
     return RotationIndexerResult{
         .lattice = indexed_lattice.value(),
         .search_result = search_result_,