The film's notion of taking the story to its Jekyll and Hyde roots (and, in the process, echoing such modern devil-inside-me takes as Altered States, which Hulk both visually and thematically evokes) is a good one.
"Hulk" also tears a few pages out of Paddy Chayefsky's "Altered States" with its isolation tanks, twisting limbs and trippy hallucinations (jellyfish hover over a desert plain, frogs explode, neon-colored cells multiply under a microscope), yet it can't reproduce the love story between two geniuses that was at the core of Chayefsky's terrifying tale.
As represented by the title, Hulk isn’t a physical thing – it’s a mentality, an idea, manifest of the materials implicit evolutionary connotations (an equally appropriate title had already been used, that being Ken Russell’s Altered States).