Josh Hartnett Is in His Dad Era Josh Hartnett Is in His Dad Era

The actor, who has spent more than two decades in the movie business and now stars in the thriller “Trap,” discussed fatherhood, fame and his love of the French New Wave.

Josh Hartnett has never made a movie that his children can see. “I would love to,” he said. “I just haven’t been offered anything like that, honestly.”

He is especially reluctant for them to see “Trap” (in theaters), the M. Night Shyamalan film in which he stars as Cooper, a devoted father who is also a prolific serial killer nicknamed the Butcher. When Cooper takes his daughter to a pop concert — an event designed to ensnare the Butcher — those two identities intersect, with devastating consequences.

Even as he searches for an escape, Cooper spends much of the movie performing the role of a great dad. Is Cooper good in the part? “He’s a little over the top,” Hartnett said. “He’s gilding the lily a little bit.”

Hartnett aims for something subtler, more naturalistic. A star by the time he was 20, Hartnett has often held the movie business at arm’s length. An industry site once referred to him as “quite possibly Hollywood’s most reluctant ‘It’ boy.” He makes few mainstream films and lives with his wife, the actress Tamsin Egerton, and their four children in Hampshire, England, rather than Hollywood.

At 46, Hartnett has a squinty-eyed handsomeness that is undiminished (and his biceps, enhanced for the role, are frankly ridiculous), but he moves through the world with more ease now. In a room at the Crosby Street Hotel, in the SoHo neighborhood of Manhattan, he accessorized his gray pants and gray shirt with an extravagant beaded necklace, a gift from his kids.