|Full name||Leo D. Carter|
|Family||Charles Carter (father)|
Helen Carter (mother)
|School||Redwood High School|
Leo Carter is a teen agent and genius in engineering. His best friends are Emma and Skye.
- Like Emma, Leo's parents don't know he's an agent. They thinks that he attends a science club.
- Leo was believed to be an Insurgent after being found interacting with various Insurgents. However, Leo did become an Insurgent, but he was actually spying on them for Teen Agents.
- In the series finale, Leo left Teen Agents and attended Massachusetts Institute of Technology.
- He shares a lot in common with Emma Hunter.