A former model claims she was just 17 when hip-hop mogul Russell Simmons forced her into sex — and all while his pal, embattled moviemaker Brett Ratner, sat by and watched, according to a bombshell report on Sunday.

Keri Claussen Khalighi said the scary casting-couch incident happened in 1991 when she and Ratner were at Simmons’ New York home to allegedly watch a music video the men had been doing, according to the Los Angeles Times.

That’s when Simmons allegedly made aggressive sexual advances and removed her clothes, as Ratner sat nearby.

“I looked over at Brett and said ‘help me’ and I’ll never forget the look on his face,” the then-Nebraska teenager recalled. “In that moment, the realization fell on me that they were in it together.”

She continued: Ratner “just sat there and watched.”

The Simmons, who is 60, would have been 33 or 34 at the time.

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