- Country: USA
- Genres: Comedy, Family, Fantasy
- Release: 1999-05-15
- Director: Duwayne Dunham
- Writers: Jenny Arata , Robert L. Baird , Kelly Senecal
- Language: English
- Stars: Chez Starbuck , Justin Jon Ross , Courtnee Draper , Brent Briscoe , Tim Redwine , Dave Coulier , Lisa Stahl , Brian Haley (I) , Karen Maruyama , Regan Burns
- Runtime: 95 min
- Awards: 1 nomination
- AKA: O 13º Aniversário (Brazil) , マーメイド・ボーイ 僕って人魚!? (Japan) , Tritón por Accidente (Mexico) , Das dreizehnte Jahr (Germany) , Trinacty rok (Czech Republic) , '13. Yıl' (Turkey) , Сын русалки (Russian Federation) , Det trettonde året (Sweden) , The Thirteenth Year (United States of America) , O Filho da Sereia (Portugal, Portuguese Republic) , The 13th Year (United States of America) , A tizenharmadik év (Hungary) , Il bambino venuto dal mare (Italy) , Le garçon qui venait de la mer (France, French Republic) , Metamorfoza (Poland) , Ο 13ος χρόνος (Greece) , Cumpleaños mutante (Spain) , The Thirteenth Year
- Plot: When Cody Griffin turns 13, things are going good. He is a star swimmer, he is getting interest from a girl named Sam, and he has a supportive family. Then he discovers that he may be turning into a fish. He also discovers who his true friends are.
- IMDB:tt0200208
The Thirteenth Year Cast · · · ALL
Duwayne Dunham
Director
Justin Jon Ross
Jess Wheatley
Dave Coulier
Whit Griffin
Kristen Stewart
Girl in Fountain Line (uncredited)
Brian Haley
(I)
Coach
Stephanie Chantel Durelli
Mermaid
Richard Tanner
Doctor Schwartz
Regan Burns
Joe