I NEVER knew how grateful I would be for Father Ted’s neutralisation of the f-word. F*** is banned in all right-thinking newspapers for fear that it will frighten the servants, but the sitcom’s Irish alternative, “feckin”, is somehow innocuous. At least I hope it is, for I’m going to need it.

Colin Farrell, an astonishingly pretty 26-year-old Irishman considered to be Hollywood’s next big thing, uses it as the fundamental building block of his conversation. Indeed, in some sentences it is the one word I am sure that I understand. Farrell mutters in such a clogged and guttural accent that he would surely be thought to be overdoing it even if he was playing an inebriated Oirishman in Carry On Paddy.

The funny thing is that this is not the mellifluous Irish voice that he chooses for his interview on the special features portion of the Minority Report DVD. Nor, as far as I know, has he ever used it on screen, not even on Ballykissangel, a Sunday night entertainment as Irish as the BBC could make it, in which he played horse-mad Danny Byrne. In his first lead role in Hollywood, as Bozz, the rebellious but saintly Vietnam-bound cadet in Tigerland, he perfected a highly believable Texan accent, and in Spielberg’s brilliant Minority Report he played the future cop on Tom Cruise’s tail as a gum-chewing American. As Bullseye, the baddy in Daredevil, he sported a Dublin accent, but it was a comprehensible one. And now in the CIA training camp thriller, The Recruit, he’s as American as a hamburger once again.

But the part that he has determined to play this morning is the wild and crazy Dubliner. He is upstairs in one of the city’s smarter hotels and, I’m telling you, there’s a feckin’ party going on up there. Down below, the British and Irish publicists, plus his personal PR from Hollywood, listen resignedly to the whoops and scuffling. It is not yet lunchtime but the booze has flowed.

“Get the feck up here,” Farrell tells a latearriving pal, disregarding his minders’ view that this is a working day rather than a get-together for his mates. I am wished sincere good luck when my turn comes to face him.

Farrell is slumped on a sofa, pint of lager half empty in front of him. He wears a woolly hat, much unattended facial hair and heavy-duty arm tattoos. His posse has, however, retreated to the bar at the back of the penthouse and has quietened down. It is clear that I am to get a different interview from the riotous chats that he has been giving the “babes” from the Irish newspapers. It will be different, too, from the dialogue faithfully reproduced in this month’s Playboy, in which Farrell talks about “his tangles with prostitutes, the celebrity images he masturbates to (Marilyn Monroe, Linda Fiorentino), drugs he’s sampled , why he’s happy about his foreskin and his best guess as to his co-star’s sexual orientation (Cruise is straight)”.

Not coming from an adult magazine, you see, the man from The Times deserves a more adult interview. Sincerity, conveyed through the authenticity of his accent, is the order of the day. I am not complaining. It is refreshing that Farrell makes no claims for The Recruit beyond the fact that it is an accomplished thriller about a version of the CIA that most of us abandoned when we read The Quiet American.

“Listen,” he says. “We weren’t making a cutting-edge feckin’ movie and it wasn’t a doccy film. The training programme? Give me a feckin’ break. Jesus, no. This is a piece of fiction. You will get your handout saying ‘Delving into the CIA for the first time, this magic thriller . . . .’ Delving into nothing.

“It is a piece of fiction and, one hopes, entertaining fiction. It does not deal with the problems within the CIA or any other federally funded agency.”

For him, the best things about the film were his co-stars, Bridget Moynahan, whom he was in grave danger of falling for, and Al Pacino, whom he could not resist either: “He was such a good feckin’ friend to me.”

But daunting to play against?

“Ah, Jesus I was s******g myself. I’m a ballsy little p**** sometimes, but even I wouldn’t have had the balls to expect to share a set with him and see him do his thing at such close quarters.”

In his young career, Farrell has already sampled a fair cross-section of Hollywood’s biggest stars. Pacino and Kevin Spacey, who picked him for his film Ordinary Decent Criminal, represent the artists and craftsmen, as at home on a stage as on a soundstage. In a class of his own was Cruise, with whom he barely had even a cup of tea on Minority Report. He describes him as “more of an entrepreneur”. At another extremity lie Bruce Willis, his co-star in Hart’s War, and Samuel L. Jackson, whose action movie, S.W.A.T., he has just completed. Farrell says he would place himself in the latter camp, if only out of fear of “sounding like a p****” if he compared himself to the first lot.