Well, this is certainly something to sing about.

Crazy Ex-Girlfriend has had some incredible guest stars stop by to sing a song or two in West Covina with Rebecca Bunch (Rachel Bloom)—Ricki Lake, Amber Riley, Lea Salonga to name just a few—but they've just landed arguably their biggest star yet. E! News can exclusively reveal that the legendary Patti LuPone will be stopping by for an episode later this season.

In the 10th episode of season two, slated to air in the new year, LuPone will play a pivotal person from Rebecca's past that she rediscovers when she returns to her hometown for a family celebration.