A former inmate firefighter harboring a grudge against Sharon returns to carry out his revenge.

The crews respond to the scene of a train crash where the rescue has the potential to spiral out of control when they discover the train is full of illicit cargo, and Robin, an enigmatic modern-day train hopper, helps injured patients.

The station 42 and third rock crews respond to a deadly explosion at an abandoned mine. Meanwhile, Bode faces a difficult decision that could have serious consequences

The station 42 and Three Rock crews are called to a backfire started by a private firefighting company to protect a high-end winery but instead threatens to grow out of control.