LONDON • Thirteen years ago, after receiving the worst critical thrashing of his life for the film Alexander, Irish actor Colin Farrell came up with what he felt was a brilliant plan to cope with the humiliation.

"Where can I wear a ski mask and not actually be put against the wall by a bunch of Swat cops?" he recalls asking himself.

The answer: Lake Tahoe, where he spent the next few days masked and drunk, and fighting the urge to apologise to potential moviegoers for wasting their money and time.

No anecdote fully captures a person's complexities, but this one helps explain the widespread fondness for Farrell.

A sensitive scoundrel is hard to resist, especially a movie star with the wherewithal to admit that a public excoriation was, in the end, a good thing.

"I was due a kick in the ar**. I really, really was," said Farrell, 41, during a recent interview here. "Because I was annoying. I had so much, so quick. I was so cocksure."

He has undergone a metamorphosis since then. A decade ago, he was playing the generic action hero, or trying to, but the big movie star suit was not a good fit - for his films or for him.

He drew middling reviews and cemented a reputation as a badly behaved bed-hopper with an insatiable appetite for alcohol and drugs. He entered rehabilitation the moment his last big film, the 2006 Miami Vice, wrapped.

But rather than lick his wounds or hold out to come back big, he came back soulful and small, turning in performances in the 2008 indie In Bruges and the 2009 low-budget Crazy Heart that drew accolades.

Now, he has veered sharply left, into rigorous art-house territory, starring in Greek director Yorgos Lanthimos' The Lobster, from 2015, and now The Killing Of A Sacred Deer, which opened in the United States on Oct 20.

One is about people who get forcibly changed into animals if they do not find a romantic partner. The other is about a husband and father who might have to kill a family member after apparently being put under an evil spell.

With the two films, Farrell put in the most deadpan performances of his career and landed some of his best reviews. This career arc has surprised even him.

During production of The Lobster, which earned him a Golden Globe nomination, he remembers telling co-star Rachel Weisz that he did not have a clue what he was doing.

"I said, 'It's the most boring performance that will ever be put on film. Ever.' It was just so dull," he said.

Farrell met to chat in the cocktail lounge of his hotel near Piccadilly Circus, where he has been staying while filming Disney's live-action Dumbo, directed by Tim Burton.

He has spent most of the past year on film sets and was aching to be back home in Los Angeles with his sons, aged 14 and eight.

"I say this as someone who is really aware of how fortunate I am; the world's smallest violin should not play for me," he said. "I'm just ready to step away from all of it. I just want to go on a hike and see my boys and go on a road trip."

Before Dumbo, which he said he liked working on very much - "there's fire eaters and guys walking on balls and trapeze artists and Tim Burton running around with a stick. It's genius" - Farrell was in Chicago filming Widows with director Steve McQueen.

And before that, he was working on Roman J. Israel, Esq., with actor Denzel Washington. And before that was The Killing Of A Sacred Deer, which was shot last summer in Cincinnati and, of Farrell's recent films, has perhaps affected him the most.

Written by Lanthimos with Efthymis Filippou, the film is far darker than The Lobster, and suffused with an increasingly claustrophobic dread. Farrell adopted a monotone for the part similar to that of his Lobster role, but the characters' similarity ends there.

David, his Lobster character, was doughy, inward and desperately lonely, all of which felt especially poignant coming from a live wire like Farrell, who said he felt great liberation in being so contained. "There was no attempt and no desire, as written, to be in any way cool, any way interesting, any way suave," he said.

But Steven, the heart surgeon he played in Killing, is cunning and arrogant and, by the end of the production, Farrell said, he felt very depressed.

He was drawn to the part by the same tug that pulled him to The Lobster, finding brilliance in the twisted worlds Lanthimos creates. And in Farrell, Lanthimos said he found a true creative partner.

"It's a gift to have that kind of relationship, it's easier to go further and explore other things," Lanthimos said. "This was a challenge, something more different and complex and dark, and I knew he had the understanding and tone."

For all his work on big films, Farrell has long preferred smaller films and the specific stories they can tell. When director Martin McDonagh approached him to play a hitman for In Bruges, basically throwing him a lifeline, he was scant months out of rehabilitation and almost turned down the part. McDonagh persuaded him anyway.

"The character needed to be lovable and appealing even though he's done something horrific and unforgivable. And it's easy to love Colin and to believe that sense of guilt he showed so well," McDonagh wrote by e-mail.

Farrell is glad that those days are behind him, he said, not least because sobriety has made him a much better dad.

His first son, James Padraig, was born in 2003 (the mother is model Kim Bordenave) and, initially, Farrell figured he would be his son's friend. "'Cause that's what a six-month-old grub needs," he cracked, "a 27-year-old drunk, high friend."

He had his second son, Henry, with his former girlfriend, actress Alicja Bachleda-Curus. Farrell shares custody of his sons and says he cannot think of a decision he has made in the last dozen or so years without thinking about how it would impact them.

Now his life centres on the boys, his home in the Los Feliz neighbourhood of Los Angeles, yoga ("I said I love it, I didn't say I'm doing it") and saunas ("very purifying").

He said he planned to take a long break and he was open to what is next, be it action heroes, even though he loathes guns ("Hate 'em"), or more unsexy roles in the vein of Lanthimos' films, even if he might be somewhat alone in characterising them that way.

"I still think he was sexy" in those movies, McDonagh wrote in an e-mail. "He couldn't really get rid of that without chopping his head off."

NYTIMES