50 Cent is suing his ex-girlfriend for defamation. 
Shaniqua Tompkins publicly accused Fiddy, real-name Curtis Jackson, of burning down his Connecticut mansion while she and their son Marquise were inside last month.
50's lawyer, Brett Kimmel, told The New York Daily News: "There comes a point where you can no longer sit on your hands and listen to her spread these falsehoods."
He added: "Besides hurting his reputation, they have a damaging impact on their son."
In the suit filed at Suffolk Family Court, New York, 50 claims Tompkins will not tell him where she is living and alleges she is preventing him seeing Marquise.