THIS is a sequel-by-numbers that is as big and muscular as its titular hammerswinging hunk, and equally short on sparkling repartee, ricocheting noisily between action, comedy and romance. A couple of plot twists, including the miraculous resurrection of one key character, cause almost as much head-scratching as the use of wormholes to travel between the Nine Realms. We are bamboozled with their cod-science while Chris Hemsworth swings his hammer with gusto.