As a cast member of Saturday Night Live, Bill Hader was one of the show’s great utility players, shape-shifting that rubbery face and malleable baritone into a crowded funhouse of oddball characters, from flamboyant club kid Stefon to an ever-exasperated Vincent Price. On Barry, HBO’s eccentric new dark comedy series launching Sunday with the first of eight half-hour episodes, Hader calls on every bit of mastery over that face of his in the service of one character, and what a character.

Hader’s Barry is a reluctant hit man, or at least becomes reluctant as something resembling a conscience begins to crawl out of the psychic wreckage left of Barry’s soul following deployment in Afghanistan.

But that brief description doesn’t begin to capture the weirdness that is both Barry and Barry’s motivations. Hader directs many episodes of the series he co-created and co-writes with Alec Berg (Silicon Valley, Seinfeld), and though its influences aren’t particularly hidden (lots of Dexter and Weeds, a bit of Grosse Pointe Blank, some Sopranos and big dash of Community), the sum of its parts is as singular as Hader’s wild-eyed mug.

Barry is more impressed by – even over-confident in – its own eccentricities than might be healthy for either a comedy or a hit man, but boldness is an essential weapon here. A series that has Henry Winkler’s hack acting teacher canceling class due to an unspeakable, bloody tragedy – while reminding grieving students he doesn’t do rain checks – better be comfortable with boldness.

The set-up: Hader’s Barry Berkman is a depressed, seemingly shell-shocked former Marine who, we’re told, was rescued from his own post-war aimlessness by an old family friend (Steven Root), who sees in Barry the makings of a fine hit man. Like Dexter‘s leading man serial killer, Barry‘s murderer only offs bad guys who deserve it (a bit of rationalizing that comes off as less a character trait than producer’s marketing decision).

One of those bad guys – or maybe not – is a Los Angeles acting student having an affair with the wife of a Chechen mobster, never a good idea. The assignment leads Barry to an acting school run by the has-been (or maybe never-was) Gene Cousineau (Winkler, hilarious), and soon the hit man is besotted with the acting life – the classroom camaraderie (that’s where the Community influence comes in), the romantic charms of the lovely Sally (Sarah Goldberg), even the sometimes vicious, sometimes flattering guidance of their pompous guru Gene.

Of course, leaving his old life behind won’t be easy, particularly once he becomes embroiled with the Chechen mobsters (exactly how that happens won’t be spoiled here). The entire eight-episode first season chronicles Barry’s Dexter-like attempts to lead two lives without the population of one discovering the other.

Hader plays Barry, especially initially, with a sort of befuddled, how-did-I-get-here look, Chauncey Gardiner armed to the teeth. We just have to take Sally’s instant attraction to him on faith. Like the series itself, Barry’s appeal might not have the same immediate impact on viewers. This is a show and a character that take some getting used to, mostly as we wait for Barry to get out of the way of its self-infatuation and give the rest of us a chance.

Barry debuts Sunday, March 25, at 10:30 pm ET/PT on HBO.