Colin Farrell was terrified of sober sex.
The 'Winter's Tale' star - who has been clean for eight years - admitted he initially struggled to get used to making love without alcohol and was scared by the change.
Speaking to ELLE magazine, he said: "I worried I wouldn't be able to talk, full stop. I hadn't uttered a word sober in about 15 years ... I made love to a woman about two and a half years after I got clean, and it was one of the most terrifying moments of my life.
"It was in the afternoon. The windows and the curtains were open. It was lovely, and, to be crass, it wasn't f**king.
"She was very gentle. But it was terrifying. Because I was just used to drunkenness and dark rooms and clubs and toilets and wherever."
The 37-year-old actor also discussed a fling which led to the filming of a sex tape - which he blocked from release via an injunction - and admitted he is worried his mother could accidentally stumble on it.
He added: "It certainly wasn't a validation of my prowess. The whole thing was horrifying. You know, Press Record. Taboo.
"Isn't this interesting? I was deposed for four hours explaining why I didn't want it to be released.
"God forbid it's an On Demand movie in a hotel room and my mother says, 'Oh, I haven't seen this work of my son's', and hits purchase."

Niall Horan's trip to Chelsea Football Club had to be kept a secret, says Jose Mourinho.
The One Direction heart throb has been given use of their recovery unit following major knee surgery, and the club's manager has admitted it was a struggle to hide what was happening from the band's loyal fans.
Speaking to The Sun newspaper, he said: "I was worried for a while because I thought, 'Nobody can know that Niall is at Cobham - we'll have thousands of girls at the gates!'
"Niall had seriously big surgery - an injury any football player would be scared of suffering. He really needs a good medical department.
"My kids are big fans but they haven't been to the training ground to see him - he has a lot of work to do."
Jose's children are the reason behind Niall's connection with the club, prompting him to agree to the arrangement.
A source previously said: "Niall has been welcomed into the club as if he's a Chelsea star himself.
"It's the best possible place for him to get the rehab he needs on his knee because he needs to be fighting fit for the band's stadium tour later this year."

Simon Cowell's son was "the perfect Valentine's gift".
The media mogul was with his partner Lauren Silverman when she gave birth to their first child Eric yesterday (14.02.14) and it is said he was "beaming" as he was on hand for the new arrival.
An insider told the Daily Mirror newspaper: "You couldn't take the smile [off] Simon's face.
"he was beaming from ear-to-ear. Lauren was so happy to see him when he walked in. It is the perfect Valentine's gift."
The TV talent show guru had to leave the London auditions of 'Britain's Got Talent' to fly to New York in time for the birth, and he faced a real "race against time".
A source added: "It was a race against time. Normally when a dad-to-be gets the call, they are just a few miles away - not the other side of the Atlantic."
Simon, 54, took to Twitter to reveal the moniker he and Lauren has decided on for their baby boy - confirming he would be named after the star's late father.
He tweeted: "Very happy to say Eric was born at 17.45pm. Healthy and handsome."
He later added: "Lauren in great shape. Thanks for all of your kind messages."

Prince will present the first prize at this year's Brit Awards.
The iconic pop star will be with his new all-female backing band 3RDEYEGIRL to kick off the show in style on Wednesday (19.02.14) when he makes his first appearance at the annual bash since 2006.
Speaking to The Sun newspaper, an insider said: "Prince is a big-name addition to this year's show.
"We've seen the massive crowds he has drawn at his recent London gigs so it's definitely going to be a highlight."
With the 'Purple Rain' singer signed on to present the first trophy at the ceremony next week, he could replicate his 2006 appearance by also performing at the event.
He will join the likes of Kylie Minogue when he hands out a gong, and he could share the stage with some huge names if he decides to play a track live.
So far, Katy Perry, Lorde, Disclosure, Pharrell Williams, Arctic Monkeys, Rudimental, Ellie Goulding and Bastille are a confirmed as performers for the event at London's The O2 Arena.
Meanwhile, James Corden will make his fifth and final appearance a the Brits, making him the show's longest-running host.

'Coronation Street' star Charlie Condou quit for the sake of his children.
The actor has two children Georgia, four, and two-year-old Hal with actress Catherine Kanter - via IVF treatment - and they split their time between their mother, and their father and his partner Cameron Laux.
Charlie - who plays midwife Marcus Dent - has admitted hearing his daughter tell him she didn't want him to make the commute from London to Manchester for work made him decide to quit the soap.
He told the Daily Mirror newspaper: "It was just getting too difficult. Georgia is at an age now where she was saying, 'How long are you away for this week?' And, 'When are you going to be back Daddy?'
"At my busiest I was getting home late on a Friday night and going back to Manchester on Sunday afternoon. I just wasn't getting that time with my kids."
And despite his departure, Charlie is glad to have been told that the door is open for a return to the soap if he changes his mind.
He added: "The producer said the door would be left open, so Marcus isn't going to be killed off. That's always a really nice thing to hear.
"I'm not under any illusions and saying I'm off to Hollywood. Obviously I want to do other things, but it's nice to know that I could go back in the future."

Sam Faiers has suggested it is time to move on from 'The Only Way Is Essex'.
The reality TV beauty will be part of the cast for the upcoming 11th series but insisted she has "done everything" on the show, and is looking ahead to other projects in 2014.
Speaking to the Daily Star newspaper, she said: "I am coming back for the next series of 'TOWIE' but there's a lot going on for me this year. Over the last few series, I have felt I'm going round in circles.
"I've given so much - I've had an engagement, arguments, ups and downs, brought my family and friends on the show. I've done everything you can!"
While there is speculation the blonde star could be interesting in writing a novel following the success of her ghostwritten book 'Living Life The Essex Way', Sam admitted she would like to get her family involved in a show in a similar vein to 'Keeping Up With The Kardashians'.
She added: "There's a lot going on in our family and it's kind of similar to them.
"Billie would be Kourtney and her partner Greg would be Scott. I'd probably be Kim, as she's had a few boyfriends in the past. It all fits in."

Emma Watson is a qualified yoga instructor.
The 23-year-old actress is close to completing her degree in English Literature and is looking forward to using her free time to pursue some hobbies away from acting.
She said: "When I finish my degree, I will have a lot more time to pursue other passions, and I want to figure out what those will be.
"I love having something completely unrelated to the film industry. I want to find something that will let me use my brain in another way. I like connecting people who aren't part of that industry.
"I love painting. So maybe I hone in on that and do more art classes? Or maybe something different. I'm a board two certified qualified yoga instructor."
Emma also has some professional ambitions she hopes to fulfill.
She said: "I feel like I have so much more to accomplish as an actress. I'd love to try theatre, and that's a whole other thing, and I love to sing."
And the brunette beauty is confident her studies will help her in her career.
She told Wonderland magazine: "I've read just about every important classic in English history, which has been extremely handy.
"It's helped me think in an analytical way. It's helped me see the world from new perspectives. Diving into these stories and characters has given richness in my own life.
"And now, when I read scripts or look at stories, I have these references for a larger understanding of humanity, I'm sure it will make my job as an actress more interesting."

Ellen Page has come out as gay.
The 'Juno' actress made the announcement at Human Rights Campaign's Time to Thrive event in Las Vegas, Nevada yesterday (14.02.14) and hopes being open will make a difference for people in a similar position.
She said: "I'm here today because I'm gay," Page said. "And because maybe I can make a difference - to help others have an easier and more hopeful time.
"Regardless, for me, I feel a personal obligation and a social responsibility. I also do it selfishly, because I am tired of hiding and I am tired of lying by omission. I suffered for years because I was scared to be out.
"My spirit suffered, my mental health suffered and my relationships suffered. And I'm standing here today, with all of you, on the other side of all that pain."
The 'Inception' star went on to describe love as "the most incredible gift to give".
She added: "I am young, yes, but what I have learned is that love, the beauty of it, the joy of it and yes, even the pain of it, is the most incredible gift to give and to receive as a human being.
"And we deserve to experience love fully, equally, without shame and without compromise."

Simon Cowell was worried he was going to miss his son's birth.
The 'X Factor' boss got a call from his partner Lauren Silverman to say their baby was on his way, and he faced a 15 hour journey to make it in time to be with her for Eric's arrival yesterday (14.02.14).
An insider told The Sun newspaper: "It was a very emotional experience for him - but his overwhelming emotion now is relief.
"He knows he was cutting it very fine to get back and wouldn't have forgiven himself if he had missed the birth. Obviously his number one priority at the moment is the health of his son and Lauren.
"He's so delighted that everything is OK. He's still getting his head around the fact that he's now a dad and has been texting family members and close friends."
Although he's typically calm and in control, Simon is said to have lost "his cool" when he received Lauren's call, but she "knows the signs" and gave him enough time to arrive by her side.
A friend said: "Simon was in shock when he got the call. It's not often he loses his cool but this was one of those times. Even though he didn't want to see the birth, there was no question that he'd wouldn't be at Lauren's side.
"She has had a difficult pregnancy so her health is his priority. This is Lauren's second baby so she knows the signs - she gave him as much time as humanly possible to get there.
"When he arrived in New York she was in the advanced stages of labour."

Harry Styles, Gary Barlow and James Corden enjoyed a break at Ian Fleming's old Goldeneye home.
The late author penned many of James Bond's spy adventures at the Jamaican property, and the British trio took the chance to have a relaxing few days before a busy month professionally.
Speaking to The Sun newspaper, a source said: "The boys had a great time together - full of lots of laughs and all very chilled."
According to reports, the One Direction heart throb attended yoga classes during their warm weather break, although his famous friends opted out.
After their brief time away, the trio will now be jumping back into work, with the Take That singer continuing his work on the band's upcoming return.
Meanwhile, Harry and James will be looking ahead to the Brit Awards on Wednesday (19.02.14), which will mark the comedian's final time hosting the annual event.
While Goldeneye was where many of Ian's 007 tales were written, it was later bought by reggae icon Bob Marley, and is now owned by Island Records boss Chris Blackwell.

Matthew McConaughey was "floored" by his lines in 'Dallas Buyers Club'.
The actor lost 42lbs to play AIDS patient Ron Woodroof in the movie - for which he earned his first Best Actor Oscar nomination - and says when his character had to admit he was dying it had a profound effect on him.
He said: "My most surprising moment during filming was when Ron says, 'Look, I'm dying'. Saying that word, 'dying' floored me. To face that not as a concept, but as a reality."
The actor has come a long way in Hollywood, but he still has fond memories of working on his debut role in 'Dazed and Confused'.
He added to People magazine: "Summer of '92. I had the time of my life and got a $320 cheque every day, which was about six times more than I was making waiting tables at the Catfish Station [restaurant in Houston, Texas]."
Meanwhile, Jared Leto also stars in 'Dallas Buyers Club' as a transgender woman with AIDS and says the key to his role was understanding her humanity.
He said: "Finding her voice and walk helped, but it was really about finding a piece of her heart."

Ellie Goulding is taking her mother to the BRIT Awards.
The 27-year-old singer - who is nominated for British Female Solo Artist and British Single of the Year for both 'Burn' and 'I Need Your Love' - wants to make her mum Tracey "proud" and has invited her to attend the prestigious music ceremony on February 19 at London's O2 Arena, where she will also be performing.
She said: "My mum's coming to the ceremony so I want to make her proud. It's the first time she's been to anything in all the years I've been doing this. And my brother's coming too."
Ellie first won the Critics Choice trophy at the Brit Awards 2010 and confessed she didn't "acknowledge" the accolade because she was preoccupied worrying about gigs she had lined up.
Talking about her pre-Brits career, she told Radio Times magazine: "Things were trundling along for me. I was doing sporadic shows. I remember finding out about the Brit Award but being so stressed about rehearsing for this little tour I was doing. I was too anxious to even acknowledge I had won it."