ActingWilliam DuffyWilliam Duffy is an actor.Known forThe Mentalist2008CRIMEBeverly Hills, 902101990DRAMAThe West Wing1999DRAMAHeroes2006SCI-FIFull filmographyThe Mentalist2008CRIMEBeverly Hills, 902101990DRAMAThe West Wing1999DRAMAHeroes2006SCI-FIIt's Always Sunny in Philadelphia2005COMEDYScandal2012DRAMABosch2015MYSTERYThe O.C.2003DRAMAParenthood2010DRAMABlast from the Past1999DRAMASniper 32004DRAMA