Lightman investigates the death of six miners in a coal mine explosion; he believes foul play may have been involved, so he puts his own life at risk to uncover the truth. Meanwhile Foster and Torres work pro bono on an FBI case.
A blast from the past pulls Lightman into a dangerous game of cat and souris testing his loyalty. The Lightman Group look into a death threat from a high school student.
Ria and Cal question a former gang leader who claims to be rehabilitated. Meanwhile, Eli and Gillian look into the death of a firefighter who was killed in the line of duty.