Chris Brown is reaching a breaking point … he’s fighting back against allegations he’s a serial rapist and abuser … and his lawyer’s taking shots at a movie studio for pushing what they say are straight-up lies.

The singer’s attorney, Levi McCathern, tells TMZ … it’s shameful Warner Brothers Discovery is propping up dubious sexual assault claims against Chris to make money off his reputation.

Chris’ lawyer says CB is tired of laying down and taking all the crap from anonymous accusers telling lies about him in lawsuits and cheesy documentaries … which is why they’re firing back at WB with a $500 million lawsuit.

Investigation Discovery’s “Chris Brown: A History of Violence” docuseries includes allegations from a Jane Doe who claims CB raped her on a yacht outside Diddy‘s home in Miami … but Chris has always denied the claim, and his lawyer says they provided WB with proof the woman’s claims were bogus.

McCathern says that’s why it’s irresponsible for Warner Bros. to include the claims in the documentary … he says folks will always try to make a quick buck off celebs with false allegations, but says the onus is on the studios to weed out the BS.

The docuseries includes a slide at the end saying Chris’ lawyer denied the accusations … but McCathern says that’s simply not enough.