Much like TRUE, SAGA was a men's adventure magazine that sprang out of the dwindling pulps era and florished until the early 1970's. While occasionally sporting a pictorial or pin-up, it's focus was more on the adventure side of things. It wasn't until a last ditch effort to stay alive that the magazine delved deeper into glamour and pop culture themes.
Their May 1964 issue featured a "book bonus" that was far afield from the mainstream historical and military tales. Pierre Boulle, a Frenchman who had written the now-famous The Bridge of the River Kwai, published a science-fiction story where, in the far distant future, apes ruled over man. Originally titled La planète des singes, it was translated into English as Monkey Planet, then in 1964 as a Signet paperback with its most familar title, Planet of the Apes.