Tatum, star of the film "Magic Mike," plays a tap-dancing sailor. Here is a clip of him singing a number strangely reminiscent of "There Is Nothing Like a Dame" from South Pacific:
The film is written, directed and produced by the Coen brothers.
The plot involves a mysterious group calling itself The Future, which kidnaps the star (Clooney) of a big Golden Age Hollywood historical epic in mid-production, potentially costing the studio a fortune.
Here is the first trailer from "Hail, Caesar!":