Plot summary
Most of Scorpion escorts Walter to his hometown in Ireland to help his parents with the blessing of Megan's cenotaph on Pattern Day for her one-year remembrance memorial. Toby stays at the garage to aid Happy with her chelation treatment and convince her to have a big wedding. Meanwhile, the Irish tradition is broken when Walter discovers the nearby lake is about to erupt, which would result in a poisonous gas cloud of carbon dioxide threatening the entire village. Cabe and Toby, via cell phone, try to ease the tension between Walter and Tim, who must work together to save the townsfolk. Also, Walter makes amends with his childhood bullies by fighting them, earning their respect.
Credits
Adapted from Wikipedia contributors, List of Scorpion episodes. HTML formatting and reference markers removed.