Eddie McDowd has been terrorizing his school and his town for many years picking on little kids and other teenagers he doesn't like. One day after he picks on a new kid he meets up with a mysterious drifter who somehow knows about Eddie. As punishment he turns Eddie into a dog. The only way he will ever get back to his human form is to perform 100 good deeds. The only one who can hear Eddie speak is the last kid he bullied.

Eddie decides to return to his home only to discover that his parents have moved out and their memories of him are gone.

Eddie falls for a poodle named Gigi. When he becomes love sick the Taylors think he's ill.

Justin gets ready for Halloween, but his fun is turned into a real nightmare when he forgets to chain Eddie up and is grounded.

Justin is upset when he doesn't make the basketball team so Eddie talks him into giving out some trash talk.

Eddie is excited when Justin gets tickets to see a movie that Eddie likes. Unfortunately they can only go if Justin passes a test from a no nonsense teacher.

Justin has a crush on an older student,Danya, the only problem is he's too nervous to talk to her. When Justin sees her washing her Mustang,Eddie feeds him lines about the car to impress Danya. She asks Justin to go to the dance with him and he accepts.Meanwhile Qwen has narrowed her date choices down to 6 guys, but she's one tough date! Her strict standards leave her without a date for the dance. Justin brings Eddie with him in the car so that he can give him pointers during the dance. Danya confesses to Justin that she used him to make her boyfriend, Flaco, jelious. Flaco finds out and just as he is about to dump the punch bowl over Justin's head, Eddie desides to take a little spin in the Mustang and hits the table, knocking Flaco over and dumping the punch on HIS head. Qwen settles with Spike as a date and Justin's just happy that he's with Danya, even if she just wanted to use him.

Eddie causes a man to fall into a pond then suddenly a golden retriever rescues the man. but when eddie revives him he thinks eddie was the one who saved his life and eddie gets a reward.

It is April Fools Day and it`s raining real hard so Justin and Gwen`s schools are closed. Someone is pulling pranks at the Taylor house. Gwen, Eddie, Justin and mom get caught in the pranks and they all think it`s dad but he was on t.v. Then, Justin figures out it was mom who was pulling the pranks.

Eddie joins a K-9 police unit. Justin and Qwen prove they can get along.