From Bradley Cooper to Brad Pitt, singer-turned-actress Lady Gaga really knows how to pick a leading man!  E! News has learned the Chromatica artist is in talks to join Pitt in the upcoming action thriller Bullet Train. No deal has been made yet and negotiations are still in early stages. Based on Kotaro Isaka's book Maria Beetle, the film is about five assassins who find themselves on a train under mysterious circumstances. Thus far, Gaga's role is unknown, but it certainly sounds like the film will open up a brand new acting genre for the triple threat, who has already scored a Golden Globe for the spooky series American Horror Story: Hotel and an Oscar nod for...