Carmack will play Tim, cousin to Teri Hatcher's Susan, who arrives at Wisteria Lane to help his relative out with her taxes. The show's producers are also looking to cast a teenage version of the character who will appear in flashbacks.
Carmack had a recurring role as Marissa Cooper's troublesome boyfriend Luke Ward in The OC from 2003 to 2004.
The actor has also appeared in TV shows Smallville and CSI: Miami and films Lovewrecked and Just My Luck.
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