Patrick was born and raised in Suriname, at the time one of the constituent countries within the United Kingdom of the Netherlands. As Suriname achieved independence, Patrick left for Europe and joined the French Foreign Legion. During his time in the Legion, Patrick used his position to supply black marketeers with weapons. Following their use in a genocidal campaign, the weapons were traced back to Patrick and he was court martialed and given a life sentence. During his incarceration, Patrick was aware of a recruiter for a mercenary organization who could get him out of gaol. Umbrella bartered with the French for Patrick's freedom and enlistment in their Umbrella Biohazard Countermeasure Service, where he was offered the additional role as a Monitor, to be paid extra for intelligence gathering.
In September 1998 Umbrella became concerned about the spread of t-Virus around Raccoon City and began training its soldiers to handle the situation. On September 25 the outbreak grew extensively due to drinking water contamination, and the force was sent in the following day. The observers were given additional orders to wipe away evidence linking Umbrella to the disaster. On the early hours of October 1, Patrick made his way into Raccoon General Hospital in search of their t-Virus vaccine research. There, he was attacked by Sgt. Nikolai Zinoviev, a fellow observer who wanted credit for destroying the vaccine research evidence. Zinoviev was distracted by Cpl. Carlos Oliveira, who was searching for the vaccine as a means of treating a friend. This allowed Patrick to pull the pin of his hand grenade, intent on killing Zinoviev along with himself. Zinoviev managed to jump out of a fourth storey window and survive the fall.
Tyrell has an alternate death scene if the player as Carlos goes into the basement before level 4F, in search of a vaccine for Jill Valentine's t-Virus infection. Tyrell, who is attempting to open a safe at the time, warns Carlos of a traitorous UBCS agent with white hair, implying Zinoviev. After his remark, the safe he is opening reveals itself to be booby-trapped, and Tyrell is killed in the resulting explosion.