Pieter "Adolph" Vorstedt was Arjen Rudd's right-hand man and the secondary antagonist of Lethal Weapon 2. He was a South African diplomat and head of security for the South African consul in Los Angeles. Like Rudd, he also hates blacks which was common during Apartheid in South Africa.
Pieter Vorstedt is Rudd's trustworthy right-hand man who helps to eliminate his enemies at all cost. He is a very skilled knife thrower when he throws his knife at Riggs' leg, and he is also a martial artist when he battles with Riggs. Alongside his boss Rudd, Vorstedt is racist towards black skinned Africans.
Vorstedt was in Arjen Rudd's office when Hans came in to tell him he lost the shipment of krugerrand. Rudd seems to forgive him stating that sometimes things don't go as planned, but suddenly he orders Vorstedt to kill him, which he does by shooting him in the head, and disposes of his body with plastic on the floor.
Later after wrapping up Hans in plastic, Rudd showed Vorstedt Roger Murtaugh's profile which he managed to steal at some point previously, and orders him to handle it any way he can. Vorstedt and some henchmen sneak into Murtaugh's home. They gag and tie him and his wife up with duct tape and mention to him that it's just been a warning to him and the other officers on the case to stay away.
The next day, Vorstedt was coming down the stairs with Rudd when the officers of the Los Angeles Police Department on the case showed up and proceed to arrest him and the others. He overhears Murtaugh call his partner Martin Riggs by name, familiarizing himself with the detective. He watches as Rudd reveals to the police his and Vorstedt's diplomatic immunity, in which neither can be arrested or charged.
Vorstedt is surprised to see Riggs make an entrance in Rudd's office and can only stare as he tells all the diplomats to stay away from him and his country. Then he randomly points his gun at each diplomat until Riggs shoots the fish tank and lets water spill loose along with the fish. Rudd gets furious and demands Vorstedt to clean up the mess, but he stares at the door seemingly plotting a scheme in his head. Later while Rudd's office is being cleaned up, Rudd warns Vorstedt about the piece of paper from the notepad had been taken Riggs, which would indicate to Rudd that that's why Riggs was there in the office before they got back, just before Rudd sends Vorstedt and some other henchmen to kill the detectives working on the case.
Later, when Tom Wyler is doing crunches in his home, Vorstedt breaks in and has a chat with him before he shoots him in the head. At the same time, a bomb he secretly planted on the diving board of Meagan Shapiro's swimming pool detonates as she is about to dive into the pool. Finally, a more dangerous explosive is implanted at Tim Cavanaugh's house, which explodes and kills him, Jerry Collins, Moss, and Friesen in the explosion.
Later, he knocks out Riggs after he dropped off Rika Van Den Haas at her apartment, which he and two henchmen proceed to kidnap and subsequently drown. He reveals to Riggs that he murdered his wife Victoria Lynn by mistake, by running her off the road, thinking Riggs was in the car, and covered it to look like an accident. Then he walks away leaving his men to let Riggs drown and die. However, Riggs escapes, and kills the two henchmen.
At Rudd's house, Vorstedt interrogates Leo asking for the money he swindled from them, which he receives severe beating for failing to answer his questions. He escapes when he finds out Riggs is pulling the stilthouse down with him, as Riggs and Murtaugh rescue Leo.
At a shipping dock where the Alba Varden cargo ship is located, after Riggs and Murtaugh kill several of the crew members, Riggs and Vorstedt engage in a hand-to-hand combat after he throws a knife into Riggs' leg. At first, Vorstedt appears to have the upper hand, until Riggs eventually gets the knife out of his leg and stabs him in the stomach, but instead of killing Vorstedt right there with the knife, Riggs lets him go and walks away.
With his remaining strength, Vorstedt gets himself up and points his gun at Riggs. However, before he can fire, Riggs presses a button of a cargo container remote. Vorstedt looks up just in time to see a cargo container come crashing down on top of him, thus crushing him to death.
Vorstedt is indirectly mentioned during love's scene between Riggs and Lorna Cole.
He is the first antagonist to be killed by Riggs.