The mood of the photo essay is a strange one: Jackie Gleason’s soon-to-be hit show The Honeymooners was about to hit the airwaves, but the star’s look in the pages of that 1955 issue of LIFE was melancholy. The entertainer, as the magazine explained, had “just become, by financial standards at least, history’s greatest comedian.” He was raking in millions between his weekly Jackie Gleason Show and new contracts with Buick and CBS for The Honeymooners. “No other actor in the world,” the magazine declared, “ever had it so good as this 39-year-old, Brooklyn-born comedian with a 265-pound body, a bellowing voice and a superb instinct for theater.”
But Gleason, who was born 100 years ago on Feb. 26, 1916, was an exacting perfectionist behind the scenes. He often found himself managing feelings of despondency when his team failed to meet expectations:
This meticulous side may have come as a surprise to some of LIFE’s readers, who were certainly more familiar with Gleason’s outsize public persona than with his private self—but one doesn’t earn the nickname “Mr. Saturday Night” without outworking his competitors. And though he was gravely serious on set, Gleason had no trouble celebrating the finer things (like custom-made suits, fine cuisine and generous helpings of scotch) during his downtime. Of the comedian, who died in 1987 at 71, LIFE wrote: “A man of boundless appetite, Gleason figures that you only live once and might as well live it up.”
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter @lizabethronk.