"A Christmas Car-Roll" -- On Christmas Eve, when Walter chooses work over spending quality time with his friends, he falls down the stairs and hits his head. As he lays unconscious, he enters a dream world where Team Scorpion never existed and he meets his guardian angel, on SCORPION, Monday, Dec. 18 (10:00-11:00 PM, ET/PT). Pictured: Elyes Gabel, Katharine McPhee, Riley B. Smith. Photo: CBS ÃÂ©2017 CBS Broadcasting, Inc. All Rights Reserved | Episode 4.12 - A Christmas Car-Roll | Promotional Episode Photos | Season 4 | Scorpion | Gallery