Nikki Castillo

While decommissioning an old nuclear missile, an accident causes the team to endure exposure to toxic vapour while trying to prevent the nuke from detonating. Paige confronts Happy about constantly tagging along with her and Walter.

Team Scorpion's job to find sunken treasure goes awry when Walter and Paige's boat explodes, leaving them lost in the middle of the Pacific Ocean surrounded by sharks.

A device that can prevent a nuclear meltdown is tracked through the Los Angeles sewers; Walter learns to listen and not offer advice to Paige; the team meets their new neighbour.

On Valentine's Day, Team Scorpion must help a doctor and pilot who are trapped inside a helicopter; Toby and Happy wait for news on their fertility results; Sylvester realizes that he may have feelings for Florence.

On Christmas Eve, Walter becomes unconscious after falling down the stairs and enters a dream world where Team Scorpion never existed.

Team Scorpion heads to the bayou to track down a cagey alligator to stop a deadly virus; Paige teaches Walter the concept of the "white lie"; Walter hits Cabe with a tranquillizer gun, and Toby must save his life.