Before he was Tony DiNozzo, Michael started out as Theo Huxtable's roommate on The Cosby Show. He then spent time in The City (formerly the ABC soap Loving) and then opposite Jessica Alba in Dark Angel.
McGee: Rule number 70 - keep digging till you hit bottom. Abby: McGee! There is no rule 70. McGee: Well, I-- Abby: You just made up a rule. This McGibbs thing has really gone to your head. I don't even recognize you right now.