The former O.C. and Prison Break guest star has joined True Blood as Bill’s wife.

The actress will be playing Caroline, the wife that Bill never returned after becoming a vamp during the Civil War. We have briefly seen a flashback of the character during season 1, not played by Lucio.

A day full of True Blood scoop! And more to come soon, as the producers are on the lookout for an actress to play Sam’s mom and a mysterious beauty to shake things up.

Wowza.

The Former Prison Break star is set to join the cast of HBO’s True Blood, THR.com is reporting.

The actor will join the show as a series regular playing Tommy Mickens, Sam Merlotte’s long lost brother who works at a Tire Depot in Arkansas.

Allman was also a series regular on Prison Break, playing Lincoln’s son in all four seasons. He has recently appeared on AMC’s Mad Men and FX’s It’s Always Sunny in Philadelphia.  

Season 3 of True Blood is due to begin airing in June 2010.