Scott Patterson

Scott Patterson, who played Luke, Lorelai's on-again, off-again love interest on Gilmore Girls, has joined the cast of 90210, TVGuide.com has learned exclusively.

Check out photos of the 90210 cast

Patterson will play Jack, the biological father of West Bev badboy Liam (Matt Lanter). Patterson will appear in multiple episodes when the CW teen soap returns in 2010.

Jack comes to L.A. after a stint in prison, looking to earn some seed money and settle down by opening a tackle shop on the marina. It's music to Liam's ears, as he sees his dad's return as an opportunity to finally get out of his stepfather's house.

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Patterson is no stranger to the CW. In addition to owning the most popular diner in Stars Hollow on Gilmore Girls, he also starred on the short-lived Aliens in America.