When I refer to David Schwimmer's Run Fatboy Run as "a modern-day screwball farce," that's a nice way of saying it's outrageously predictable, unabashedly sappy, and completely formulaic through and through. You know where the movie is going from frame one, and it sure doesn't take a lot of detours getting there. But the phrase "screwball" probably wouldn't have come to mind if Run Fatboy Run wasn't at least a little bit funny. Which it is. So if you don't mind an amiable-yet-seriously familiar 90 minutes -- and you're a big fan of British actor Simon Pegg -- I'd have no problem recommending the flick. Even if I'd never come close to calling it something brilliant.

The effortlessly likable Simon Pegg stars as one of those lovably lazy sad-sack types that you only come across in comedic films: Despite the fact that he left his pregnant fiancee (Thandie Newton) at the altar five years earlier, Pegg's "Dennis" is one of those losers we love to root for. (How a doofus like this ever scored a catch like Thandie Newton -- and then abandoned her! -- is one of the film's sillier conceits.) So when his former flame's smarmy new boyfriend (Hank Azaria) mentions that he'll be running in an upcoming marathon, Dennis senses a shot at redemption.

That's pretty much it: One affable schnook (who, yes, is seriously out of shape) aims to win back the love of his girl (and the respect of his adorable 5-year-old son) by running in a massive marathon that'd defeat even an experienced runner. In Dennis' corner we have an amusingly sleazy best pal (Dylan Moran) and a good-natured landlord called Mr. Ghoshdashtidar. So clearly we're working in the realm of "big-screen sitcom" material, and if you walk into Run Fatboy Run expecting some sort of deviation from the "underdog story" formula, you've come to the wrong place. (Hell, even the screenplay feels familiar! One key line is this: "Yeah, I may be fat but I can lose weight. You'll be an asshole forever!" As if we haven't heard this silly little quip a thousand times by now.)

But as was often the case in even the flightiest of old-school screwballers, Run Fatboy Run is elevated by a speedy pace, a colorful demeanor, and some really amusing performances. It certainly doesn't rank as highly as his work in Shaun of the Dead or Hot Fuzz, but Simon Pegg proves here that he could be "watchable" doing just about anything. His role here is little more than an old Bill Murray character, but Pegg still manages to squeeze an impressive amount of chuckles from such old-hat material.

Pegg's fans would dig the flick for his performance alone, but the comedian is backed by a small handful of solid people. As Pegg's ridiculously smug adversary, Hank Azaria is (as always) very funny -- as is Dylan Moran as our hero's semi-sleazy best friend. The material they're working with is hardly comedic gold, but there's a lot of wit and chemistry when Pegg and Moran share the screen. Toss in some light lifting from the lovely Thandie Newton and a surprisingly funny turn by Indian actor Harish Patel -- and you've got an ensemble that's better than the material, frankly.

Directed by David Schwimmer (yes, that David Schwimmer) and co-written by Pegg and Michael Ian Black, Run Fatboy Run is so conventional and predictable that it simply couldn't have happened by accident. Which is why I choose to look at the flick as an unapologetic throwback to the days when comedies didn't have to be all that original -- just as long as they were funny.