The Hulk is just Jekyll and Hyde retold. That story is an old one and has its own analyses over the decades, not really Marxist though, more about good and evil within man, and how one chooses between them, if at all.
But we could turn it towards a Marxist analysis in saying that the proletarian has the seed for revolutionary thought and action within them, but it only comes to fruition when something materially changes so that the proletarian can no longer continue to exist under their capitalist mode of existence.
This doesn't have to be something fancy like gamma rays or whatever that serum Jekyll/Hyde drinks; it could be any workplace incident that changes a worker's life for the worse. This is when we get class action, literally class action suits, protests, strikes, maybe even socialist revolution.
Ah yep that triggered the full memory for me...it was a book called Tikki Tikki Tempo: https://en.wikipedia.org/wiki/Tikki_Tikki_Tembo