She was portrayed by Pik-Sen Lim.
In Hong Kong, the Killer Janitor kills the interrogator who was looking for the key in the Casino. The next day she kills former CIA agent Titus Fisher, who has a piece of the key with sniper rifle disguised as a vacuum cleaner.
Later, in Pegasus' house, Killer Janitor throws knives at Johnny English but Johnny shields himself without being stabbed by the her. Johnny English then chases her down but ends up almost strangling one of the agent's mother, twice.
While golfing she kills Artem Karlenko, her traitorous golfer, for giving information to Johnny. The spy, who was present, got away in the Karlenko's helicopter but Killer Janitor used her Gatling gun to shoot it down.
In Kate Sumner's house, Killer Janitor chases after English and seemingly kills English. In reality English ran to contact Tucker to go to Swiss Alps.
At the end of the movie, English is rewarded by the Queen to have his knighthood restord but the Killer Janitor, disguised as the Queen, tries to attack English. English pursues and attacks her. However, he really captured Queen Elizabeth. He realizes this when the Royal Guards are revealed to have captured the Killer Janitor.