It’s true that Richard Curtis’ Pirate Radio is set in 1966, during the period when official British radio stations did not carry rock and roll. And it is also true that it’s set on a seafaring broadcast operation, a stand-in for one of many real-life such entities that proliferated at the time to feed the public desire for rock radio. But if you’re expecting Pirate Radio to actually be about that time and that circumstance, you are much mistaken.

Over his 25-year writing career, Curtis has somehow managed to find success with two radically different audiences. On the one hand are his witty but ultimately sentimental romances like Four Weddings and a Funeral, Notting Hill, and his 2003 directing debut, Love Actually. On the other, his largely episodic comedic efforts, most notably his collaborations with Rowan Atkinson like Black Adder and Mr. Bean. Pirate Radio falls squarely in the latter category, employing its “inspired by true events” concept as little more than a loose framework for a whole lot of masculine carrying on, most of which is wonderfully funny, even if the story could just as easily have been about a bunch of rowdy soccer players.

And this is really the context in which Curtis works best: scenes that take advantage of blistering wordplay and his fondness for various types of stock characters. We get an easily-likeable hero in 18-year-old Carl (Tom Sturridge), who comes aboard after difficulties at school because his godfather, Quentin (Bill Nighy), is the ship’s owner. Among the deejays-at-sea are The Count (Philip Seymour Hoffman), a cooler-than-thou American expatriate; Simon (Chris O’Dowd), a nice-guy type who perpetually gets stepped on; and Dave (Nick Frost), who alternately works to help Carl lose his virginity and steal his girlfriend. Add a resident dimwit, Thick Kevin (Tom Brooke), serving the function of Black Adder‘s Baldrick, and you’ve got the recipe for great comedy.

It’s a recipe that succeeds, provided you’re not expecting anything more than laughs. Perhaps out of a sense of narrative obligation, Curtis throws in a few conflicts that the lads must contend with. Externally, there are the efforts of a British government official (Kenneth Branagh) to shut down Radio Rock’s nose-thumbing operation; internally, The Count curries a rivalry with Angus (Rhys Ifans), the preening deejay superstar who returns to the ship after time abroad. Regularly scheduled snippets showing the boys and girls (and adults, too) listening back in England are an attempt to suggest that this historical footnote really moved and affected people, but it’s a token effort in something that largely feels like two hours of sketches.

Those sketches are generally so entertaining, though, that it hardly matters. Curtis gets most of his mileage out of the fact that Radio Rock is an all-male operation — the crew’s lesbian cook notwithstanding — and therefore they generally behave the way a bunch of guys stuck together with no authority and high on their own sense of rebellion would likely behave. They play games, like a celebrity-ID competition in which Carl, much to his dismay, is paired with Thick Kevin; they lounge around on deck and share “I never” revelations, which eventually becomes a way to “out” the others’ embarrassing stories. The terrific cast gets a ton of mileage out of Curtis’ snappy, profane patter, making their interactions so lively that for much of the running time, it feels like you could hang around with these fellows as long as you’d be allowed.

Unfortunately, stuck with no obvious answer for how he should end such a yarn, Curtis opts to turn the last 20 minutes into a maritime disaster epic, as the ship faces a Titanic-like catastrophe. Even then, Curtis manages to turn some potentially maudlin moments into great bits of comedy, particularly when Carl tries to help a deejay who can’t part with his precious records, even in the face of impending death. But those moments still have to battle for time with plenty of shots of water pouring through bulkheads, and a “will they or won’t they make it” artificial drama that seems tonally out of place.

Pirate Radio doesn’t need such extraneous material to keep an audience engaged. Like his characters, Richard Curtis rebels against a prevailing artistic sensibility — in this case, that really good jokes require a story to keep them afloat.