- ""Move it! Come on! Move!""
- ―Uli to hostages
Uli is hired along with a crew of about a dozen henchmen to rob the Nakatomi building in Los Angeles of its $640 million dollars in negotiable bearer bonds. The plan was cooked up by Uli's temporary employer, Hans Gruber, and seemed simple enough to pull off. Take hostages, steal the loot, and escape after blowing up the roof of the building. The police will think the bad guys were killed in the explosion, and they certainly won't wonder why the roof spontaneously blew up in the first place.
We first seen Uli and the other terrorists inside the Pacific Courier truck and went with them to the elevator. He was among the men who took everyone in the 30th floor hostage. Afterwards, the henchman helped Heinrich and Marco on moving missiles on the 35th floor roof access and assisted them on planting C4 charges on the 35th floor to destroy the roof of the building.
Uli was in the reception floor with Eddie when Sergeant Al Powell arrived at the building, hiding by the elevators with a gun in case Al would approach them. He was still there when the LAPD SWAT team was going in. Once he and Eddie set up to get ready to attack them, Uli sees some candy bars on the food stand and took one to eat it. While eating a bar, Uli listened to Theo's intel as four men were about to enter the building. After Hans tells Uli and Eddie to just wound the SWAT team, Uli hits one in the shoulder while Eddie shoots another SWAT member using a blowtorch in the legs.
After that, Uli and Eddie went to guard the hostages in the 30th floor. When Hans and Karl returned with the recovered detonators stolen by John McClane, Uli went up to finish setting the C4. Once it was done, he returned to the 30th floor. Before Uli can gather the hostages to the roof, Hans listened to Richard Thornburg's interview of Lucy McClane and realized that Holly Gennero is John's wife, causing Hans to look the picture which shows John McClane and his family thus putting Holly in danger as well the hostages. After he takes Holly, he tells Uli to lock the hostages on the roof and return. Uli gathered the hostages to the roof, to be killed by the C4 he helped place.
Uli ushered all of the hostages to the roof's helipad and followed them up to lock them on the roof so they couldn't escape when Hans detonated the C4 they planted under the roof earlier. After he got all the hostages up there, he slipped away and ran back down the stairs, but as he opened the door, John McClane was waiting there with his Beretta 92 handgun, using it to pump four rounds into Uli's chest, killing him instantly, and leaving his body in the stairwell, to be blown up with the rest of the roof, later. Uli was the eighth man in Hans's group to be killed by McClane. Had McClane not waited for him to come down the stairs, it is quite possible Uli would have survived, like Kristoff (possibly) or Theo.
- Many believe Uli only said one line in the movie (Move it!!! Come on!) to the hostages, but he also said another (Got It.) to Hans when he threw him a bag of detonators. Leong claims that his lack of lines is due to him being a stuntman, not an actor.
- Uli enjoys candy bars as he is seen taking a Crunch Bar during the S.W.A.T team shootout in the lobby and eats a Mars Bar a few moments after. The scene was actually improvised by actor Al Leong, as he felt the scene could use some comic relief. This is one of the trademarks of Die Hard, much like Al Powell's liking for Twinkies. Leong made sure to ask director John McTiernan for permission, claiming that he didn't want to get yelled at for taking food.
- Al Leong had previously played an ill-fated henchman called Endo, a year earlier before the first Die Hard film in another iconic action movie thriller Lethal Weapon (which coincidentally featured a film score by the first three films' composer Michael Kamen). He would later play a similarly ill-fated and nearly-mute henchman on the television series 24.
- He is the only Asian member of Hans' gang and the only member, besides Hans, to have facial hair.