If Bill Hader had been born 100 years ago, he could have been a matinee idol. The same talents that made him a brilliant clown on Saturday Night Live for almost twelve years would have made him a heartthrob in the studio era: the elastic extremities, the syrupy tenor voice, the chiseled face that is almost symmetrical. Many of Hader’s best impersonations on SNL were plucked from vintage showbiz: Vincent Price, John Barrymore, Peter Falk, Peter O’Toole, Rod Serling, Alan Alda. His transatlantic accent could cut glass; he crooned film noir lines like a young William Holden. It was not difficult to imagine him as a leading man who had simply dropped into the wrong decade.

When Hader finally quit SNL in 2013, he went out on a high, having developed one of the most popular original characters on the show. He and writer John Mulaney created a pop culture monster in Stefon, a nightlife correspondent who listed increasingly nonsensical attractions at various clubs. The character highlighted Hader’s strengths: absurdist wordplay, scampish mischief, genuine ebullience. But when Stefon hit, it also left Hader in the classic SNL double bind, where the success of a single sketch both cements a cast member’s fame and threatens to swallow their entire body of work. One sketch too many, and you are forever the Ladies Man, or Pat in perpetuity.

Hader wriggled out of the show just in time. Deciding against doing a Stefon movie, he started to stretch his range: Kristen Wiig’s depressive brother in the glum Sundance darling The Skeleton Twins, the milquetoast romantic hero opposite Amy Schumer in Trainwreck. While he took on an array of personae in the TV series Documentary Now!—a sharp, goofball collection of parodies of acclaimed documentaries, such as Nanook of the North and The Kid Stays in the Picture—it still felt like an offshoot of SNL. Until this year, we had yet to see what Hader could do on his own, with original material.

Which brings us to Barry, a new half-hour sitcom that debuted on HBO in March. Although set in the present, the show is a direct descendant of 1940s noir films, in which an isolated man wanders through a venal Los Angeles, dealing with con men, gangsters, and a smart-cracking blonde. In this case, the man is a former marine who has retooled as a hit man, and the blonde is a plucky ingenue he meets in an acting class. Hader is not only the star of the show but its main creative force. He co-wrote many of the episodes (along with Alec Berg, formerly of Seinfeld and Silicon Valley) and has directed several himself. If he was born to be an Old Hollywood star, Barry is where he finally gets the opportunity to show it.

The premise of Barry is outlandish, but Hader sells it well. After returning from the Middle East, Barry cannot cope with his civilian existence. He is clinically depressed, to the point of not being able to leave the house. Then an old mentor—a schlump named Fuches, played with comic largesse by Stephen Root—convinces him that he might want to work for him as an assassin. The military taught him how to kill, and he turns out to be very good at it. But he can’t justify the work the way he could when he was a soldier. As one character, a policewoman who pursues Barry throughout the series, says, “We are not the same, Barry, because I am a cop, and you’re a fucking murderer.”