Hollow Man is the antagonist of the Academy Award Nominated movie Hollow Man and the direct-to-video sequel Hollow Man 2. He's actually a parody of another invisible villain, but his character sparked a horror franchise and a song named after the character.
The first movie depicts the evolution of a brilliant and lovable man into a psychotic killer where his colleagues led him to his demise, much to their grief.
The original hollow man is a brilliant but lustful scientist named Sebastian Caine who leads a team of scientist who tries to make an invisible serum to the U.S. Army. He's a kind, generous, and a class clown in the team and he was the first to formulate the antidote that can make anything invisible visible again.
He volunteers himself to become invisible, not knowing the consequences. His antidote worked on previous experiments, but it didn't worked on him, much to his dismay.
During his invisible state, he's always disturbed by his transparent eyelids, preventing him from getting some sleep because of the lights easily penetrating his eyes. He was locked up in his lab for safety sake and to avoid leaking of their experiments to the public. Being held alone in the lab's holding pen was enough made him depressed, also paving the road to his insanity. He eventually escapes and kills the army personnel that has been plaguing his career and experiments, raping women and making some pranks along the way. At the apex of his insanity, he brutally murders some of his former colleagues, but is killed by some of the remaining ones.
HOLLOW MAN 2The second movie introduces Michael Griffin, a soldier who was experimented with the invisible serum and has gotten AWOL since. It's said that he becomes invisible by letting light pass through his body, getting his organs radiated in the process which will kill him eventually. Michael's search for an antidote led him to a series of manhunts that caused him his demise. Early in this film he was used to commit assassations for the government.
The heroes discover this and they managed to kill Michael Griffin and the government agents that were involved with Griffin.