Special Agent Caitlin "Kate" Todd (portrayed by Sasha Alexander) is a fictional character in the CBS drama NCIS.
Biography Caitlin was a former Secret Service Special Agent; she was hand picked to protect the President. She broke the rules by dating a co-worker, and chose to resign, before she was fired. NCIS Special Agent Leroy Jethro Gibbs made a fast move and hired Caitlin right after she resigned.
Cailtin had a great relationship with Gibbs, he was her mentor and believed she could become a great agent. Kate had a lot of respect for Gibbs, and worked well with him.