In 1949, Esposito was working on staff at Lev Gleason. "I was there for a while and then I shopped around. Went to school first, naturally, and then went up to Timely Comics future Marvel Comics, as it was transitioning into its 1950s iteration, Atlas Comics. ... Stan Lee interviewed me and said, 'Okay, you can start here as a penciler.' So my job was to pencil so many pages a week for my salary." His first confirmed work there is as penciler and inker of the war comics story "Heat of Battle" in "Men's Adventures" #6 (Feb. 1951), though he had done much uncredited work in the interim, including his first professional inking. He recalled,