Gwendolyn "Gwen" Wu is a recurring villain of the 2008 television animated series The Mighty B and also one of the three secondary villains of the 2010 animated horror film Alvin and the Chipmunks: The Demonic Possession and a member of a biker gang. She is voiced by Jessica DiCicco, who is well known for voicing Malina from The Emperor's New School, Flame Princess from Adventure Time, Maggie "Margaret" Pesky from The Buzz on Maggie, Olette from Kingdom Hearts 2, and Penelope Patterson from Kick Buttowski.
In 2000, Gwendolyn, along with two bikers named Portia Gibbons (Grey DeLisle) and Gary (Jason Marsden), travels to Monterrey Park and stops in a convenience store. In the store, Gwendolyn takes to hassling customer named Simon Seville (Matthew Gray Gubler), having both Portia and Gary restrain his older brother named Alvin Seville (Justin Long). Having grabbed Alvin's red wallet when he attempted to throw it to Simon, Gwendolyn taunts Simon, making Simon grudgingly ask for it back and address her as "Gwen".
After Alvin accidentally mangles their motorcycles as revenge for troubling him and Simon, Gwendolyn and her fellow bikers follow the two boys back to the suburbs of Riverside. Despite being reluctant to participate in her friends' plan to burn down the haunted house after siphoning gasoline from a red Mazda van, Gwendolyn, however, after being reassured by Portia that nobody will get injured, wanders off to look around. Going into the haunted house, Gwendolyn nonchalantly begins toying with some of the equipment lying around on the second floor, eventually climbing up onto the third floor that leads to the attic. Finding a rope and rake used to hoist dry leaves, Gwendolyn begins swinging from it for fun, catching the attention of, and annoys Gary, who demands Gwendolyn to come down this instant, so they can help Portia in her revenge plans. Unseen by Gary, Gwendolyn was ultimately grabbed by Donald Walls (posing as Theodore Seville) and pulled back into the haunted house, where Theodore/Donald stabs her to an attic rafter by the throat with a sharp pitchfork. Shortly, before Theodore/Donald kills him too, Gary finds Gwendolyn's corpse, which Theodore/Donald later moves. Gwendolyn "Gwen" Wu's corpse was eventually found and taken away by the paramedics.