Barry Livingston Barry Livingston

Former child star Barry Livingston, who played Ernie, the youngest of Fred MacMurray's boys on My Three Sons, has been cast on the October 31episode of ABC's Castle, titled "Cops and Robbers." Barry, now 57, will play Abe, an unsuspecting bank customer who his held hostage in a vault along with Castle (Nathan Fillion) and his mother, Martha (Susan Sullivan), during a botched bank robbery.

"Castle's trying to help Martha get a loan for her acting school when the bank is taken over," previews executive producer Andrew Marlowe. "Beckett gets involved from the outside trying to negotiate the safety of all the hostages. Along the way there are lots of twists and turns." (Hmm... sounds a lot like the set-up of Susan's short-lived 2006 ABC series, The Nine.)

Barry, who'll also be popping up on an episode of ABC's new sitcom Suburgatory, has made the rounds on ABC's schedule in recent years, with guest spots on Desperate Housewives, Grey's Anatomy and Eli Stone. He has also penned a new book titled The Importance of Being Ernie in which he reveals how he survived the stigma of being America's #1 Nerd.

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