George Reeves was one of the earliest actors to play Superman and was almost certainly the most beloved until the almost-identically-named-but-not-quite Christopher Reeve came along. But Reeves never relished the role and felt playing a TV superhero was beneath him — according to The Telegraph, he was frequently drunk on-set and would say things to his co-star Phyllis Coates (Lois Lane) like “here’s to the bottom of the barrel, babe,” before drinking some more.
By the time he died on June 16, 1959, Reeves was in the toilet, professionally and personally. He had been typecast due to his Superman role, as studios didn’t want to give him serious film work anymore, seeing him as nothing but a children’s TV guy. He gained weight and became severely depressed. He was found with a bullet in his chest, although no one is sure how it got there. Either he shot himself intentionally, or his girlfriend (or one of his ex-lovers) did. Or perhaps he accidentally shot himself while high on painkillers (he had been in a bad car accident months before). It could have been something else entirely. Unfortunately, detectives didn’t do much detective work. They decided it was a suicide without even dusting for fingerprints. They also tampered with the evidence (and Reeves’ body) so much it’s likely impossible to ever learn the truth. Either way, whether it was Reeves himself or someone else, somebody did what even Doomsday could not: killed Superman and kept him dead.