Psycho Duck is the final episode of the third season of The Proud Family and is the original series finale, airing on August 19, 2005.
Penelope rescues a handicapped duck named Chester from drowning in the river while hanging with her usual friends in addition to Duke. Chester then becomes clingy and extremely protective of Penny. His aggressive personality becomes too much for the family to deal with so Oscar, with the help of Bobby and Felix attempt to get rid of Chester at Trudy's request without Penny knowing. Turns out, Chester belonged to a wealthy family and was always accustomed to being spoiled. He was returned to his rightful owners by Wizard Kelly who received a reward of $1 million.
This episode aired, alongside The Proud Family Movie.