Jeff Conaway

Jeffrey Charles William Michael Conaway (October 5, 1950 – May 27, 2011) was an American actor. He portrayed Kenickie in the film ''Grease'' and had roles in two television series: struggling actor Bobby Wheeler in ''Taxi'' and security officer Zack Allan on ''Babylon 5''. Conaway was featured in the first and second seasons of the reality television series ''Celebrity Rehab with Dr. Drew''. Provided by Wikipedia