Gregory Alan Williams (Born on June 12, 1956) is an actor and author who portrayed Garner Ellerbee in Season 1, Season 3 to Season 5 as a cast member, recurring role in Season 2 and Season 8 and a cast member in the spin off Baywatch Nights. He is currently playing Robert "Mac" MacCready in the American drama Greenleaf and is also She is also set to play a role in a detective movie called The B Team along with other Baywatch cast members Jeremy Jackson, David Chokachi, Gena Lee Nolin, Jaason Simmons, Michael Bergin, Alexandra Paul and Kelly Packard.