Justin Bieber I Really Am ... "KING of the World |Justin Bieber

Justin Bieber will almost certainly get lucky tonight ... because TMZ has learned he just surprised girlfriend Selena Gomez with the most romantic surprise ever.He's corralled the entire Staples Center in L.A. for a screening of the movie "Titanic"... just for the two of them.Sources connected to the Biebs tell us .. Justin hatched the idea after seeing the movie"Mr. Deeds" -- where Adam Sandler