Greg Tiernan (born on June 19, 1965 in Dublin, Ireland) is an Irish-born Canadian animator, director, producer and voice actor. He is the Chief Creative Officer and co-founder of Nitrogen Studios. He was the director of Thomas & Friends from 2008 to 2012. He began work directing the series after the CGI transition, taking over from Stephen Asquith.
He was born in Ireland and started Nitrogen Studios in 2003 with Nicole Stinn.
Other work includes, "The Land Before Time", "An American Tail", "All Dogs Go To Heaven", "Happily N'Ever After", "Trollhunters" and "Sausage Party".
- "Sausage Party" (2016)
- "City in Crisis" (2015)
- He is married to Nicole Stinn.
- He has been working in the animation industry for twenty-seven years.
- Tiernan is a fan of the Railway Series. So much in fact, that he owns a copy of both The Island of Sodor: Its People, History and Railways and Sodor: Reading Between the Lines.
- According to an interview with SiF, Greg Tiernan says he would like to remake Pop Goes the Diesel and Dirty Work. And, if it was his choice, he would reintroduce every character ever introduced.
- Tiernan was involved in the animation of "Happily N'Ever After", the last film in which George Carlin played a part.
- He, Nicole Stinn, Ellery Van Dooyeweert, Kevin Pavlovic, Arlyn Bantog and Jeff Bailey all worked on "Sausage Party".
- He, Nicole Stinn, Sara Martin, Kallan Kagan, Marianne Culbert, Travis Gagne, Mitch Pollard, Ellery Van Dooyeweert and Steven Mark Chen all worked on "Trollhunters".
- He, Alejandro Mayén, Mercedes Espinosa, Einat Glixman, Anna Sztejner, Eberhard Haar, Mayra Arellano, Loretta Santini, José Luis Orozco, Julia Pistor, Achim Schülke, Petri Hanttu, Angela Quast, Katja Brügger, Liliana Barba, Beata Wyrąbkiewicz, Rocío Garcel, Mari Maurstad, Chie Kōjiro and Peter Weis have all worked on "Rugrats".