Lady Gaga is already a superhero, just ask any of her Little Monsters. If the “Poker Face” star does indeed come on board to play Harley Quinn in Joker 2, it would simply seal the deal. On Monday (June 13), The Hollywood Reporter revealed that Gaga was in early talks to play the ever-so-unhinged Quinn in a musical sequel to Joker, with Joaquin Phoenix in discussions on a return in the lead role. None of this is confirmed, though stranger things have happened. Joker was a hit, becoming the first R-rated film to pass $1 billion at the box office, while Gaga has an impressive and growing collection of cinematic roles, including central, starring performances in House of Gucci and A Star Is Born. Sources tell THR that “Warners has yet to close a deal with the actor, with the two sides deep int...