Dr. Sebastian Caine, played by Kevin Bacon, is a character in the film Hollow Man.
Dr. Sebastian Caine, an ambitious molecular biologist who has developed a serum that can render the subject invisible. Instead of reporting his success to the military, Sebastian lies to an oversight committee which includes his mentor Howard Kramer, telling them he is close but needs more time. He convinces part of the team to go right into human testing without military authorization, keeping the rest in the dark. The procedure is successful and Sebastian turns completely invisible. He enjoys sneaking around the lab in order to scare and play pranks on his fellow co-workers, including molesting Sarah. The team becomes concerned that Sebastian is taking it too far. The procedure to return him to visibility fails, and he is almost killed.
Sebastian is quarantined in the laboratory due to his condition and the other researchers construct a latex mask for him to wear around the lab. Unable to cope with the isolation, he defies instructions and leaves the building. After he drives to his apartment to retrieve some lab supplies, he notices a female neighbor undressing and rapes her inside her apartment. Linda warns Sebastian that if he leaves again, she and Matt will tell the committee about the experiment. Ignoring their threat, Sebastian assembles a device that runs a video loop of his heat signature in his quarters. He leaves the lab again and spies on Linda and Matt, becoming enraged when he sees them about to have sex. Sebastian, becoming increasingly unstable, later kills a dog being used as a lab animal in a fit of rage.
The team discovers that they have been watching a recording and that Sebastian has been leaving the lab without their knowledge. Linda and Matt go to Kramer's house and confess their experiments. After they leave, Kramer attempts to alert the Army, but Sebastian, who followed Linda and Matt to the house, kills him before he can contact anybody. The next day, Sebastian waits until the whole team is inside the lab before he disables the phones and the elevator codes except for his own. He begins to murder team members one by one, with Janice being his first victim.
Linda and the others hide in the lab, while Matt and Carter take tranquilizer guns to hunt for Sebastian using thermal imaging goggles. Sebastian mortally wounds Carter before getting into a fight with Matt. Linda saves Matt. Sebastian then kills Sarah and Frank, and locks an injured Matt and Linda in the freezer, leaving them to die. Linda constructs an electromagnet using a defibrillator to open the door, then gathers materials to assemble a flamethrower. Meanwhile, Sebastian builds a makeshift bomb that will destroy the facility after he leaves.
Just as Sebastian enters the elevator, Linda fires the flamethrower at him. Sebastian escapes and the two fight. Before Sebastian can kill Linda, Matt strikes him with a crowbar. Sebastian recovers and approaches Matt and Linda from behind with the crowbar but Matt deflects the blow, throwing Sebastian into a nearby circuit box, shocking him and rendering him partially visible. Linda and Matt find the bomb, but cannot stop it. They attempt to climb a ladder in the elevator shaft to escape as the bomb explodes. Sebastian, despite his injuries, grabs Linda's ankle. He pulls her off the ladder and onto the top of the elevator. Linda disconnects the elevator cables, causing Sebastian to fall to his death down the shaft.