He was first mentioned when Rianne ask her father: Roger Murtaugh, if she can go to the party, but was grounded for smoking pot. He was describe as having dimples on his face, but her father told her they were pits and describe when he smiles he can see right through him, then told her no, much to her disappointment. One rainy night, Mark and Rianne are inside his car parked just outside of her house. The two make out in the car when Rianne hears a knock on the window. Unable to see through the fog, she wipes the window to find a man with blond hair who immediately frightens her.
It can be assumed at this point Mark tried standing up for Rianne, only to be shot by the suspect, and left his body to die on the front lawn, as stated by the police dispatch.