Mac and Kelly (Rogen and Byrne) are living in wedded bliss in their dream home with an adorable baby when a fraternity moves in next door. So Mac and Kelly introduce themselves to leaders Teddy and Pete (Efron and Franco), showing that they're cool and asking them to keep the noise down. But they don't. So when Mac and Kelly call the cops, it turns into all-out war as the frat boys and the married couple play a series of escalating pranks to keep the upper hand. And neither is willing to give up quietly.

The film is fast-paced and gleefully coarse. And while some gags simply don't work, the lively pacing and snappy characters keep everything moving, so we don't have to wait long until we're laughing again. The plot is essentially just a series of increasingly crazed practical jokes that play out in raucous set-pieces, but this helps it build momentum right up to the requisite epic party climax. Meanwhile, each character starts with a stereotype then twists it until it's unrecognisable.

Efron and Franco are hilarious as the provocateurs, especially when they turn their rage, and more intriguingly their affection, on each other. Rogen and Byrne sharply capture the sense that Mac and Kelly still have plenty of youthful spark even though they're at the point in life where they should settle down. Clearly these four have more in common than they think, and around them are an array of scene-stealing side-characters from a wide-eyed fraternity pledge (Roberts) to the sharp-tongued university administrator (Kudrow).

Even with its gaping holes (why doesn't anyone else call the cops?), the script makes some nice observations about growing up and leaving partying behind, recapturing youthful enthusiasm, learning to take responsibility and the joy of getting older. Even more provocative is the way each character must balance their expectations. But this is essentially just a silly, surprisingly sweet movie that somehow manages to get it right.

themes, language, sexuality, violence, drugs

16.Apr.14