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.

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

Power is knocked out in Los Angeles, and the team must help a teen pilot and his girlfriend who are lost over the Pacific without any radio contact; Walter must look after a group of Ralph's classmates; Cabe tries to tell Allie that he loves her.

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.

Team Scorpion must use their high IQs to win a softball game; Walter's secret night out with Florence puts Toby and Happy on edge.