'Scorpion' Season 4 Cast: Shantel VanSanten to Play Toby's Genius Ex-Fiancée

"Shooter" star Shantel VanSanten is the latest addition to CBS' action series "Scorpion." She has been cast as Toby Curtis' (Eddie Kaye Thomas) ex-fiancée, Amy Berkstead.

Facebook/ScorpiononCBS"Scorpion" airs Mondays at 10 p.m. on CBS

The character is a brilliant geneticist who Toby met at Harvard while he was in Medical School. They used to be engaged, but she called it off because of Toby's gambling habits and immaturity. Though they are now both married to different people, his beautiful and intelligent ex will still have an effect on him. It goes without saying that her reappearance in Toby's life will affect his marriage to Happy (Jadyn Wong).

To make things worse, Amy married pop-psychologist Quincy Berkstead (Jeff Galfer), who happens to be Toby's nemesis.

VanSanten is set to appear in multiple episodes of "Scorpion." She is expected to make her debut on the show next year, in episode 13. It should premiere in January after the holiday break.

For the time being, Toby and the rest of team Scorpion will have to help a father and daughter whose plane crashed nearby. Next Monday, in an episode titled, "Crime Every Mountain," the team will have to improvise when their plans go askew.

Also revealed in the synopsis of next week's episode, the team will be preoccupied by Cabe's impending trial. Though his fate is not set in stone, team Scorpion's handler will struggle with the thought of having to spend time in prison. But Paige (Katharine McPhee) and Walter (Elyes Gabel) will help him get through it.

Guest cast next episode include Sonny Marinelli who has been cast as Frank, Allie Gonino as Jessie, Fay DeWitt as Ima, Dana Davis as Hadley Dine, and Luis Carazo as Ranger.

"Scorpion" season 4 episode 10, titled "Crime Every Mountain," airs Monday, Nov. 27 at 10 p.m. EST on CBS.