4. Johnny Depp - Mr Sinister
Depp has long been attached by rumour as the fore-runner for the lead in Marvel's Doctor Strange for good reason. He has an ethereal air to him that translates well to supernaturally slanted characters, or at least exotic ones (hence Edward Scissorhands, Icabod Crane, Raoul Duke, Sweeney Todd and Jack Sparrow), and it remains a missed opportunity that he hasn't played more villainous roles. Fox should steal a march on Marvel by casting Depp for the key role of Mr Sinister - one of Apocalypse's four horsemen, who created Cable in the comics - and play the mad scientist element of the character in Apocalypse. He should be presented as a renegade, having left the Horsemen in order to destroy Apocalypse, and as the key to the creation of Cable using Cyclops and Jean Grey's genes, and thus top of Apocalypse's hit-list along with the young mutant pair. The resolution of that plot would then allow for a switch-turn that revealed Mr Sinister to be a villain to take him into the Gambit stand-alone movie, as well as being a presence in the X-Force universe, and having an actor of Depp's ability and profile would be a major bonus.