Marin Hinkle by Cliff Lipson/CBS Marin Hinkle by Cliff Lipson/CBS

Marin Hinkle is cornering the market on bitter ex-wife roles.

The Two and a Half Men actress (she plays John Cryer's uptight ex) has been cast as Courtney McCallister, the bitter former spouse of Rob Lowe's Sen. McCallister, on Brothers & Sisters. She'll appear in one episode this fall, but it's likely she'll be back for more. In the episode, Courtney goes on a Larry King Live-type talk show to discuss her estranged hubby's bid for the White House - further inflaming tensions between the two.

Since Hinkle is a series regular on Men, it's safe to say that she had to get CBS and Warner Bros.' OK before committing to B&S.

In other casting news, Tom Everett Scott has sealed a deal with ABC's Cashmere Mafia to play the fiancé of Lucy Liu's character - which is a little strange since in the pilot I saw she was definitely single. I'm sure there's a very good explanation for that. Or not.