To fix a Los Angeles nuclear reactor that’s on the verge of a cataclysmic meltdown, Walter and the team must reluctantly enlist the help of a troubled former member.

Team Scorpion must find a boy from Ralph’s class who goes missing on a field trip after he accidentally has a run-in with a deadly criminal. Also, Toby gets closer…

Team Scorpion must outthink their unstable ex-Scorpion member, Mark Collins, after he kidnaps Toby and threatens to kill him unless his cunning demands are met.

Team Scorpion goes to Chernobyl to repair the decaying nuclear reactor before a catastrophic meltdown, but must also save Sylvester and Paige when they become trapped inside.