Long before 'Castle' became a ratings hit, Nathan Fillion was on 'One Life to Live.' Now Castle and Beckett are investigating a gruesome murder on the set of fictional soap 'Temptation Lane' (Mon., March 21, 10PM ET on ABC), which was actually shot on the set of real-life soap 'All My Children' with cameos from two of its stars.

Does that make any sense? All you need to know is it's got everything a great 'Castle' episode should, including guest spots from some pretty cool names and a few inside jokes.

Cleverly titled 'One Life to Lose,' the episode shows Beckett (Stana Katic) and crew getting called in to investigate an axe murder -- literally -- on the set of a popular soap opera.

'AMC' star Rebecca Budig plays (you guessed it) a soap star, but her TV husband Cameron Mathison is behind the camera here, playing director, and guest star Corbin Bernsen is playing Budig's TV love interest instead.

Mathison's character is particularly close to the crime, since the writer who gets murdered is also his wife. The there's Jane Seymour as Gloria Chambers, the victim's mother who has some secrets of her own.



It's safe to say that the drama on the set of 'Temptation Lane' rivals anything they could think up on-screen. Everyone's a suspect, everyone's an actor and, yes, everyone's a bit of a diva. Should make for a very interesting investigation.

I caught up with Fillion, Budig and Mathison to hear more about the case, and got the two soap regulars to dish on the 'Castle' will-they/won't-they debate. Fillion and Budig also teased Mathison for taking his cameo responsibilities too seriously. I guess the fake power of fake directing a fake soap opera can go straight to a person's head.

'Castle' fans: Are you excited for the show's crossover of sorts into the wonderfully dramatic world of soap operas? And 'AMC' fans, how nice is it to see Rebecca and Cameron outside of Pine Valley?



Follow Maggie on Twitter @TheTVShowGirl