McGinnis became an apprentice at Walt Disney Studios, then studied fine art at Ohio State University.
[2] After wartime service in the Merchant Marine he entered advertising and a chance meeting with Mitchell Hooks in 1958 led him to be introduced to Dell Publishing began a career drawing a variety of paperback covers for books written by such authors as Donald Westlake (writing as Richard Stark), Edward S. Aarons, Erle Stanley Gardner, Richard S. Prather, and the Michael Shayne and Carter Brown series.
[6] McGinnis's attention to detail was such that when he was assigned to do the artwork for Arabesque he requested Sophia Loren's tiger stripe dress be sent for him for a model to wear so he could get the right appearance.
[7] Since 2004, McGinnis has created cover illustrations for the Hard Case Crime paperback series.
Starting in 2016, McGinnis has painted a number of retro-style covers for reissues of books by Neil Gaiman.