Making movies has always required long hours on the set. In the 30s, before the concepts of time and a half and double time existed, working into the wee hours of the morne was not uncommon. There would be lulls between actual filming, especially for the cast. Stars sometimes had the option of retreating to their dressing rooms for a nap, or what have you. :0)
In the photo below, Bob is playing the vibraphone during a break on the set of Ever Since Eve (1937). Marion Davies, his co-star, always had musicians on the set of her movies, a carry-over from her silent picture days when music was used to help set the mood for the performers. Since Eve was Marion's last picture, I'll guess this may have been the last movie to have musicians on the set for the actors. As for Bob at the vibraphone ... just another of his many talents.
There were breaks for mealtimes, and to be sure you didn't waste time leaving the studio, the larger studios had commissaries open long hours to serve their employees with their somewhat erratic work hours. Below, we find Bob at the MGM commissary during, once again, the filming of Ever Since Eve. I'm guessing he's thinking when the photographer shows up: "Geesch, can't I ever get any peace around here!"
Even on your day off - note that's singular, no two-day weekends - you could be required to come to the studio, often for publicity purposes. In 1929, a very young and dapper (always!) Bob appears for a photo shoot featuring Fifi D'Orsay, "The French Bombshell." This is before Bob/MGM admitted there was a Mrs. Bob.
I'm just glad they all "suffered" through it and made so many delightful movies for us to enjoy these 80 years later. Their hard work, our enjoyment.
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