The Yellowstone actor is being sued by Devyn LaBella, who has claimed she was subjected to a "violent, unscripted, unscheduled rape scene" without notice on set in May 2023 while filming Horizon: An American Saga - Chapter 2.
The 24-year-old stuntwoman's team first filed the lawsuit against Costner and Horizon producers in May and have filed an amended complaint including text messages with the movie's intimacy co-ordinator, and the alleged emotions she felt after the scene.
In response, Costner's lawyer Marty Singer told DailyMail.com in a statement: "Ms LaBella was doing a rehearsal on an insert shot for a scripted scene. There was no intimacy or anything sexual in the shot.
"There was tugging on a dress while she was fully clothed in a dress with long bloomers lying down next to a male actor."
The lawyer has also alleged that LaBella - who was a stunt double for series star Ella Hunt - thanked her supervisor for "these wonderful weeks" after finishing work on the Western saga.
"Numerous witnesses have contradicted Ms LaBella's meritless claims," Singer said.
"We look forward to the swift end of this specious lawsuit.'
Court documents obtained by DailyMail.com say LaBella was hired as a stunt double for lead actress Ella Hunt and not informed or consented to the added scene, which she alleges caused "permanent trauma".
She also claimed the absence of an intimacy co-ordinator during filming.
Her suit, filed in Los Angeles County Superior Court, states the scene was not on the call sheet and Hunt refused to perform it, allegedly walking off set.
She said Costner directed actor Roger Ivens to perform the assault scene and asked her to stand in without adequate preparation or safeguards.
Kevin's lawyer Marty Singer denied the allegations, calling her a "serial accuser" and accusing her of "shakedown tactics".
"Kevin always wants to make sure that everyone is comfortable working on his films and takes safety on set very seriously," he said.
Her lawyers described the case as "emblematic of what is still a very deep-rooted issue in Hollywood" and "a clear example of male-dominated, sexist Hollywood movie production".
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