Plot summary
After a pregnant girl is found murdered in prison, Cal and the Lightman Group team help Torres clear her juvenile delinquent sister of the charge and protect her from the real killer. It turns out that the warden was running a business letting the prisoners out to rob rich peoples' homes for her so that the warden could, eventually, gain $2 million. She then had the pregnant girl, Marly, killed because the girl was threatening to expose the whole system. Cal gets her to confess inside the Lightman Group interrogation room, while having all the convicts standing outside and watching her go down. Foster and the prison psychologist seem to get romantic because at the end of the episode he walks into Foster's office with a bouquet of flowers. Torres' sister Ava takes a good step in her life and reconciles with her sister. Emily passes her driver's license test.
Credits
Adapted from Wikipedia contributors, List of Lie to Me episodes. HTML formatting and reference markers removed.