An aspiring actor has told a jury he believed “vile sexual predator” Kevin Spacey drugged him before the star performed a sex act on him while he was asleep.

The alleged victim labelled the two-time Oscar winner as “atrocious, despicable, disgusting” after jurors were shown footage of his police interview – where he broke down as he described the alleged assault.

Southwark Crown Court heard the witness had been warned that Spacey liked young straight men, but told the jury he found the idea of people having sexual encounters with others to merely further their career to be “abhorrent”.

Jurors were told the man had written a letter to the Hollywood star asking for help, which later led to the alleged incident – adding that he was “dumbstruck, starstruck by the idea of essentially meeting an idol” when he asked him if he wanted a beer.

While at the flat, the complainant said Spacey initiated a “remarkably inappropriate” hug, which made him feel “like I was being circled by a shark” before the actor allegedly put his head on the man’s crotch.

The court heard the night had ended with the man crying at a bus stop when Spacey asked him to leave following his rejection of the star’s alleged sexual advances – describing the experience as “completely traumatic and life-ruining”.

He told the officer he did not leave when Spacey had put his head in his crotch because “you just don’t want to annoy someone who’s that powerful in the business you’re trying to break in to”.

“Nothing happened that was consensual,” the man told police.

Under cross-examination from Spacey’s lawyer Patrick Gibbs KC, the barrister said “you never said no”, to which the complainant replied: “You can’t when you are asleep.”

The witness rejected claims from Mr Gibbs that he had questioned his own sexuality after the incident.

“I find this the most reprehensible line of questioning,” he said.

The witness also described Spacey as “a vile sexual predator who sexually assaulted and performed a sex act on me while I was asleep”.

Asked by prosecutor Christine Agnew KC if the defence were correct to suggest he had manufactured the allegations against Spacey to “make money”, the man said: “Absolutely not.”

Addressing how he felt that the actor had made time to meet him, the man said: “It made me feel weirdly special because it was someone saying ‘Hey, I’m going to clear out time for you this evening’.”

He told police he had eaten leftover pizza and smoked cannabis with the star before describing how Spacey had opened his arms for a hug.

The man continued: “Then he started to nuzzle his head … he was just rubbing his head into my crotch – I thought ‘this is incredibly weird’.

“I was very nervous at this point, I was just flicking through TV channels.”

Speaking about the allegation of the sex act, the man told the officer he began to feel “woozy” before saying: “Going to sleep isn’t something I would normally do – it is unusual in my behaviour just to conk out.

“I remember four to five hours later waking up – my belt was still together but my button and my zip were down and he’s just performed (a sex act) on me.”

The man initially told police he did not want to “wildly insinuate something untoward was going on”, but later told jurors: “I was taken advantage of, I believe drugged, and sexually assaulted.”

He said Spacey immediately asked him to leave after he rejected the sex act, and added: “He said I shouldn’t talk to anyone about what had happened.”

The man told the officer that others had told him Spacey liked the “young straight guys”.

He said: “I didn’t know at that point he was a predator.”

Spacey, 63, has been described by the prosecution as a “sexual bully” as he stands trial accused of sex offences against four men between 2001 and 2013.

The defendant pleaded not guilty in January to three counts of indecent assault, three counts of sexual assault and one count of causing a person to engage in sexual activity without consent.

The two-time Academy Award winner also previously denied four further charges of sexual assault and one count of causing a person to engage in penetrative sexual activity without consent.

The trial continues.