The complaint from Massachusetts State Police details an incident between Spacey and a busboy at the Club Car, a restaurant and bar on Nantucket, late on July 7 into July 8.

The busboy, who was 18 at the time, told Spacey he was 23 and studying business at Wake Forest University, according to the complaint. That night, Spacey bought him a number of alcoholic drinks, bragged to him about the size of his penis, and tried to get the busboy to go back to his house afterward, the accuser told police in the complaint.

Later, as the two stood near the piano player in the bar, Spacey reached over and began to rub the busboy's thigh, the complaint states. Spacey then unzipped the accuser's pants and rubbed his penis, both in and out of his pants, for about three minutes, he told police.

The busboy did not know what to do and did not want to get in trouble at work for drinking, particularly because he was under the legal drinking age, the complaint states. He said that he tried to shift away with his body and move Spacey's hands away with his hands, but Spacey kept reaching down his pants, the complaint states.

During this time, he was texting with his girlfriend, who did not believe what he was telling her, the complaint states. So he sent her video on Snapchat of Spacey groping him, the complaint states.

In his interview with police, investigators showed the busboy that video and confirmed his and Spacey's clothing that night.

The complaint comes more than a year after the alleged victim's mother went public with the allegations against Kevin Spacey. Heather Unruh, a former TV news anchor in New England, held a press conference in November of 2017 saying her son her son had been sexually assaulted by Spacey.

Spacey faces a charge of indecent assault and battery, Cape & Islands District Attorney Michael O'Keefe said Monday. He is scheduled to be arraigned on January 7. CNN has reached out to Spacey's attorney for comment.

Girlfriend confirms she saw the video

In a separate interview, the busboy's girlfriend told police that he had indeed texted her that Spacey was hitting on him. She confirmed that she received a Snapchat video from him showing Spacey touching the front of his pants by his crotch, though she couldn't give any more details on it, the complaint states.

Generally, videos taken on Snapchat disappear from the app after they are watched, though users are sometimes allowed to replay a video. Snapchat's law enforcement guide says that the company often cannot retrieve user content, except in very limited circumstances.

Kevin Spacey speaks with members of the press on the red carpet during Netflix's "House Of Cards" screening in Washington, DC on January 29, 2013.

After several minutes of the alleged groping, Spacey got up to go to the bathroom, and the busboy left the bar. While on his way home, Spacey texted him, "I think we lost each other," and the busboy did not respond, the complaint states.

He said that he told his younger sister what happened when he got home. She called their mother. He also returned to work the next afternoon and told his boss about the incident, the complaint states.

The accuser's younger sister told police in an interview that he was acting unusual when he got home late that night, the complaint states.

Investigators also interviewed several employees at the bar who confirmed that Spacey and the busboy had been seen together that night, although none witnessed an assault.

He said the incident was embarrassing but has not had a profound emotional effect on him, according to the complaint. He decided to come forward and tell police because he did not want what happened to him to happen to someone else, he told police.

Focus turns to accuser's behavior

In a hearing last week to determine if there was enough evidence for Spacey to be charged, his lawyers questioned a Massachusetts state trooper about the video.

Their questioning hinted at their strategy, focusing on the amount of time it took the accuser to go to police, and his behavior on and off camera.

Trooper Gerald Donovan said the accuser gave his first full statement to police on November 22, 2017. He told police that he lied about being a 23-year-old college student, Donovan said. According to the accuser, the encounter lasted about 70 minutes, during which time he consumed 8 to 10 drinks, including beers and whiskey.

The video is less than one second long. It shows a hand making contact with a shirt, but no body parts are visible in the video, Donovan said. In the video, the accuser is wearing a blue shirt, even though he told police he was wearing a red one, the trooper said.

Donovan said he learned that, before the alleged assault, the accuser gave Spacey his phone number, went outside to smoke, and went back inside with Spacey.

Under questioning from lawyer Alan Jackson, Donovan said he found no witnesses to corroborate the accuser's claim that Spacey groped him for three minutes.

"Instead of walking away or moving away or moving back or grabbing the wrist or slapping the hand, he indicated to you that, during that 3-minute time period, that he was texting and snapchatting?"

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