Gerard Butler and Jonny Weston.

There are two monster waves in Chasing Mavericks, a surfing movie inspired by the life of Jay Moriarity, the northern California teenager who in 1994 became an overnight celebrity in the surfing world after riding the infamous swells off Half Moon Bay known as Mavericks.

One is the literal mass of churning, white water – more washing machine than wave, due to the bay’s unusual reef formation – that lends the movie its name and much of its dramatic power. The other is a more figurative hydraulic – the tsunami of schmaltzy melo- drama that, at times, threatens to swamp the proceedings, which at heart are actually kind of thrilling and inspirational.

Although Mavericks is structured around the quasi- father-son relationship between the squeaky-clean Jay (Weston) and Frosty Hesson (Butler, pictured with Weston), the gruff, grizzled surfing veteran who becomes the teen’s life coach and big-wave trainer, there’s lots of extraneous plotting – which, however fact-based, is handled in such a pre-fab manner that it feels phoney.

Jay comes from a broken home and has abandonment issues around his absentee father. Jay’s mother (a fine Shue) is an irresponsible drunk, at least initially. Jay’s childhood best friend (Devin Crittenden) starts hanging out with disreputable types, threatening their friendship.

There’s also a seemingly unattainable childhood sweetheart (Rambin) and years of unrequited puppy love.

Frosty, for his part, is wrestling with balancing family life, as a husband and father of two kids, with his love of a dangerous sport.

That’s a lot for one little movie.

Fortunately, directors Michael Apted (best known for the series of Up documentaries) and Curtis Hanson (L.A. Confidential) manage to keep this syrupy tide in check, mostly by focusing on the central relationship between Frosty, who learns how to be a better father from his protegé, and Jay, who finds a surrogate dad in his mentor.

After a somewhat shaky start, the movie improves as it works its way out of the tangle of subplots to an undeniably stirring conclusion. It even manages to make its corny surfing-as-a-metaphor-for-life message somewhat palatable, although it’s not much deeper than “carpe diem”.

As Frosty, Butler is appealingly crusty. His character is a nice – and necessary – tonic to Weston’s Jay, who seems to have stepped out of a 1960s Disney movie. With his blond ringlets, buff bod and sunny demeanour, Jay is a male Pollyanna, as loath to utter an unkind word as he is easy on the eye. The surf cinematography is pretty impressive, too.

Chasing Mavericks builds, perhaps not exactly like the majestic, 12m walls of water that are its subject, but with a satisfying enough – and even somewhat unexpected – crash. Like any wave, it will carry you away, as long as you don’t try to fight it.

If you liked… Blue Crush or Soul Surfer… you will like this.