Out goes Renee Walker, in comes Michelle Dessler.

TVLine has confirmed that on the heels of Annie Wersching’s Castle encore, fellow 24 alum Reiko Aylesworth will guest-star on the ABC drama.

What’s more, Desperate Housewives vet Ricardo Chavira has a key role in the same episode; the actor revealed the castings with this photo on Twitter:

TVLine has learned exclusively that Chavira will play Alex Lopez, a popular congressman whose life may in danger, while Aylesworth is playing his astute wife, Mia.

They both appear in Episode 18, when Detective Ryan — who it was established has been working side jobs — pulls some hours at his brother-in-law Frank’s private security company, which has been charged with protective Congressman Lopez.

UPDATE: David Conrad (Ghost Whisperer) guest-stars as Frank, while Heather Mazur (Awkward, Pretty Little Liars) plays Ryan’s sister/Frank’s wife Gwen.

Teasing the Ryan-centric episode, showrunner David Amann told TVLine, “He gets involved in a situation where [he and Frank] are guarding somebody important and an incident occurs, and he is caught in the middle of it.”

Since her three-season run on 24, Aylesworth has appeared on such series as ER, Damages, Lost, Hawaii Five-0 and Revolution. Chavira’s post-Housewives credits include Burn Notice, Welcome to the Family and Bad Teacher.

Castle resumes its season, with Episode 17, on March 16.