Laszlo was one of Katrina Moorkroft's servants, serving as the butler at Moorkroft Manor. Like all of Katrina's servants, Laszlo was capable of transforming into a hideous gargoyle, and would routinely abduct male victims and take them back to the mansion for their employer to drain. Evidently, they were granted prolonged life and youth the same as her. Laszlo and another servant, in gargoyle form, abducted a construction foreman from Skycor Towers, despite the interference of T-Bone and Felina Feral. After returning to Moorkroft Manor and reverting to his normal form, Laszlo turned Felina away when she arrived at the front door to question him, claiming he hadn't heard anything unusual.
Later, as part of a trap to capture the snooping Felina, Laszlo and Otto took the drained corpse of the foreman to dump it in Megakat Marsh. Felina attempted to follow and arrest them, but the two transformed into gargoyles and captured her. He was present during Katrina's attempt to drain Commander Feral during an eclipse. When the Swat Kats intervened, he, Otto and a third servant turned into gargoyles and battled them, but Laszlo and the other gargoyle were quickly defeated when Razor dropped a chandelier onto them. After Katrina's death, he and all of her other minions aged into dust.
- Laszlo appears in the unfinished season two episode "Succubus!", also known as "The Curse of Kataluna". Although the episode never aired because it was never finished, the script exists in its complete form.
- His basic character (as well as the plot) was recycled for the Jonny Quest episode "Eclipse", where he and the other servants were combined into a single character, Andrew.