Team Scorpion must stop a sabotaged runaway subway train with Paige and Ralph on board. Also, in his attempt to impress Happy, Toby has his first boxing match.

After Sylvester scores big on The Price Is Right, Team Scorpion must infiltrate a high-end car smuggling operation about to ship bioweapons to South America.

Paige’s estranged mother calls on Team Scorpion when she accidentally uncovers a forgotten nuclear reactor on the verge of exploding.

Team Scorpion gets trapped inside a failing and dangerous biodome designed for Mars while trying to extract a pair of scientists inside.

While tracking a device that can prevent a nuclear meltdown through the Los Angeles sewers, Walter learns the nuances of listening and not offering advice to Paige. Also, Team Scorpion meets Florence, their new neighbor at the garage, after she sends a mix of smelly chemicals through their shared ventilation as a warning to keep the noise down.

Team Scorpion must prevent an incoming tsunami from hitting a vulnerable nuclear power facility, and Toby secretly helps his ex-fiancée retrieve her stolen identity.