Castle will take on zombies next Monday, prior to concluding season four with the focus on a far more pressing topic:

The man who shot Kate Beckett.

That will be the focus of the May 7 finale, "Always," as the death of an Army veteran sends Beckett on pursuit of the assassin who took her down last May. How far will Castle go to keep her safe? What secrets will be revealed? What feelings laid on the table?

ABC has released a number of photos from the finale, which will also feature the return of Judith Scott as Captain Montgomery's wife. Click through them now and let the (hopeful) countdown to Caskett commence...