Liam O'Dourke is a Sim in Hidden Springs, where he lives by himself in a small house. He works in the science career as a Useless Contraption Manipulator. He has 5 logic and 3 gardening skill points, which is 3 points away from the required level for a promotion.
Liam is friends with the "prince" of the town, Sebastian Vanderburg, as well as Ella Carlisle, and is acquainted with the "queen" of the town, Catarina Vanderburg. It is implied by his bio that he wishes to start a romance, but wonders "will he get enough time away from a book to do so?"
- Liam was originally made for promotional purposes and did not exist in the retail game until Hidden Springs was released. However, he could be downloaded along with the Kent household in The House that Grant Built, where he has two roommates, Kim Kent and Piper Hipp.
- Liam also appears in the producer walkthrough for The Sims 3: Island Paradise as the "captain" of the S.S. Nardone. His clothing and hairstyle were changed for the walkthrough, but nothing else appears to be different about him. In the video, Liam mans the helm, attends a Sim's wedding, is attacked by the Kraken, and discovers an uncharted island.
- He is one of the many Sims that appeared on the cover for The Sims 3.
- In one of The Sims 3 trailers, it showed that one of his traits is Charismatic along with Genius and Hopeless Romantic.
- Liam doesn't have a lifetime wish by default. This makes his lifetime wish randomized in each game.
- He appears on The Sims 3 website when it is down for maintenance or otherwise not working. This has earned him a somewhat negative reputation among many regular contributors to TheSims3.com's forums.
- Without the "L," his name sounds like "I am a dork."
- He is supposed to be in a relationship with Brianna during the pre-release video and trailer storyline.
- Liam O'Dourke is not created by Grant Rodiek as many people think.
- He is similar to Carter Farrell from A Cinderella Story, as a nerdy, best friend to the Cinderella character, Ella Carlisle. His position is also similar to Jaq, in human form, from Cinderella 2.
- Despite his description, he does not have the Bookworm or Computer Whiz traits.