Dennis is the deuteragonist of the 2001 TV series Stanley. He is the pet goldfish and best friend of Stanley Griff. He is a supportive fellow, and is always taken with Stanley every time they go into the Great Big Book of Everything in every episode. He teaches Stanley everything about animals. He even breaks the fourth wall by either encouraging the audience to do something fun or by asking them questions. He is shown not to like the book's theme song, especially when every time it is spoken of or even taken, fellow pets Harry and Elsie sing the theme song. Dennis is voiced by British actor Charles Shaugnessy.