Black Knight is the one of three secondary villains in animated television horror film Scooby-Doo: The Watcher in the Barn. She is voiced by Jennifer Hale, who is also voiced Samantha and Mandy in Totally Spies series. Her real name was unknown.
Black Knight, while passing through Ponyville with fellow bikers Rose Wilson (Pamela Adlon) and Crayon Boy (Richard Steven Horvitz), stops at a convenience store, where she and her friends start harassing two customers Hoagie Gilligan (Benjamin Diskin) and Kuki Sanban (Lauren Tom). Grabbing Kuki with Rose, Black Knight holds her while Crayon Boy taunts Hoagie, making him ask for Kuki's earlier thrown green wallet and call him "sir". When Crayon Boy eventually does give Hoagie the wallet, both Black Knight and Rose let Kuki go.
Shortly, after having their motorcycles damaged by Kuki as revenge for troubling her and Hoagie, Black Knight and her companions follow both Kuki and Hoagie to Sweet Apple Acres, where Black Knight keeping a lookout signals for her friends to come out of hiding when the coast is clear. Along with Rose, Black Knight begins siphoning gas from Applejack's orange Volkswagen bus, planning on using the fuel to set fire to the Sweet Apple Acres barn. When Rose fills up a canister of gas, Black Knight grabs it and heads to the barn, where she finds Crayon Boy, who had earlier wandered off, happily swinging from a suspended rope and pulley on the second floor of the barn. Demanding Crayon Boy to get down and help her, Black Knight fails to notice Fauntleroy Donaldson, grab him, take him inside, and kill him in cold blood with no remorse. Going into the barn to look for Crayon Boy, Black Knight climbs up onto the second floor and finds Crayon Boy dead, having been pinned to a barn rafter by the throat with a sharp pitchfork.
Staring in horror at Crayon Boy's corpse, Black Knight is ultimately attacked by Fauntleroy who impales by the stomach with a sharp pitchfork. After killing Black Knight in cold blood, Fauntleroy rolls her corpse onto the bottom floor of the barn and hangs her upside-down from an apple tree. Black Knight's corpse, still suspended from the apple tree, is later found by the authorities and taken away by the paramedics.
- In the original Scooby Doo x My Little Pony novel, Black Knight is a minor villain that doesn't appear until page 223.