In the mid-1920s, he became a production assistant and story consultant to Irving Thalberg at MGM, whom he succeeded after his early death, becoming one of the most important and powerful film producers of the era.
He became the stuff of tabloid legend when, at age 42 the tubby, balding executive suddenly married sex goddess Jean Harlow, his junior by 22 years. Just two months after their marriage, Harlow left Bern alone at their home to visit her mother, but when Bern did not join her as planned an investigation found him dead. He was sprawled naked in front of a full-length mirror in their bathroom, drenched in her favorite perfume, shot through the head with the revolver nearby. He left an apparent suicide note, which read ‘Dearest dear, unfortunately this is the only way to make good the frightful wrong I have done you and wipe out my abject humiliation. I love you. Paul. You understand last night was only a comedy.’ It was also revealed that prior to his marriage to Harlow, Bern apparently had a common-law wife, Dorothy Milette, who was reportedly mentally unbalanced. Witnesses reported a woman answering Milette’s description visited Bern the night of his death. Milette was last seen boarding the ‘Delta Queen’ in Sacramento, days later her body was found in the Sacramento River. Rumors that Paul was either gay or impotent also swirled after his death. Although the official cause of Bern’s death was found to be suicide, rumors circulated that he may have been murdered. The potentially scandalous circumstances surrounding the death were concealed for years by MGM. Harlow would not speak of Bern’s death for the remainder of her short life. Entombed at Inglewood Park Cemetery in LA.