Jak & Daxter: The Precursor Legacy
Keira's role in Jak & Daxter: The Precursor Legacy is primarily to assist Jak in his quest to find the Sages and defeat Gol and Maia. She does this by creating different gadgets throughout the game in exchange for Power Cells. She also talks to Jak using the Communicator she built. It is established that she has feelings for Jak which he reciprocates as shown when they almost kiss during the game's finale only to be interrupted by Daxter.
After the opening scene in Jak II, Keira is missing until half way through the game where she is found working at the cities racing grounds. She has been working on repairing the time machine that brought them to Haven City to help send them back to their time 500 years earlier.