This entertaining creature feature broke box office records in South Korea with its combination of family-friendly horror and suspense. A tale about a giant, mutant monster that slides out of the Han river in Seoul causing mayhem is the stuff of B-movie flicks, but this pulls it off with fun and panache.

When a US army medic orders a Korean junior to pour gallons of formaldehyde into the Han river it causes a marine creature to mutate into a large giant monster squid-like thing. The dozy, slow-witted Gang-Du is working in his dad's noodle shack on the river banks, when this slimy, green amphibian emerges out of the water for a snack, stampeding the assembled masses and causing widespread terror and havoc.

Eventually, when the creature jumps back into the waters, Gang-Du has the horrible realisation that his daughter Hyeon-Seol is coiled in a tentacle. He, his father and estranged siblings, college-boy brother and archery-champ sister, set out to track the monster down to its lair. It's a mission that will require them to negotiate military roadblocks, deal with underworld criminals, avoid bounty hunters, as well as face the monster itself.

The clearly talented director Bong Joon-Ho is getting into his stride with this his third feature. As in his previous films, he is particularly adept at creating tension and mood through composition. For instance, many sequences take place in and around the Seoul sewage system (where it usually seems to be raining). The subterranean world of city infrastructure like bridges and tunnels have an eerie, spartan majesty. They are the perfect domain for a monster. The big, orchestral soundtrack when combined with the elegant visuals adds to this sense of epic grandeur.

Such a film rises or falls on its special effects and the huge lumbering beast looks great, even after making many appearances. It moves in a very organic way, lurching along in giant strides and using its long, whiplash tentacle to swing from bridges, or pluck people up and dash them to the ground.

The suspense is done well, aided by a good ensemble cast. Some of the comedy doesn't always come off. For instance, occasionally histrionic elements seem silly. But the fact that the film doesn't take itself too seriously is part of its appeal. It's a horror that's not that horrible, and makes up for any deficiencies with its style and bad taste humour.