- "I never felt safe anywhere on Earth except for Scorpion, and now not even there."
- —Sylvester to Megan
"Revenge" is the eleventh episode of the first season of Scorpion. It aired on December 8, 2014.
Sylvester is seriously injured when he accidentally triggers an explosive device during an investigation, and Team Scorpion search for who is responsible.
At the beginning, a group of masked people enter a safe manufacturing company with a bottle of water, guns and explosives. Shooting two people dead, they open a safe and set off exploding boxes. Drew asks Paige to dinner and the gang, especially Sylvester, are all uncomfortable that they eavesdropped on the conversation. At the crime scene, it is revealed that Agent Gallo knows the investigating officer, Interpol Agent Simone Taylor from a case they worked together years before. Simone tells the team that they are starting to get a good reputation. O’Brien and Happy explain why and how the water was used to break into a high tech safe.
However, Sylvester tells Walter that he feels this sort of case is not something that they are built for. Seconds after this, Sylvester accidentally touches one of the explosives that the criminals left behind, trying to rearrange them, and it explodes, throwing Sylvester through that air. The team soon learns that Sylvester is in critical condition, and they won't know the extent of the injuries until he wakes up. Walter’s sister, Megan, who is doing physical therapy at the same hospital that Dodd is in, keeps track of his progress while team Scorpion investigates the crime and tries to catch the people who injured their friend.
Cabe warns Walter that he needs to remember to not let revenge or anger cloud his thinking. Agent Taylor calls the criminals the “Ghosts” and explains that the law enforcement community has been trying to catch them for over a decade. The team is having a hard time dealing with Sylvester’s life threatening injuries and Toby butts heads with Walter. Afterward Happy comforts Toby, who tells her that Sylvester has always been there for him and when he was 16, he sold his entire Super Fun Guy comic book collection to pay Toby's rent. Megan learns that Sylvester was saved because a piece of shrapnel, which should have gone into his heart, lodged in his sternum instead. After his surgery, Megan tells the surgeon that Walter will want to see the piece of shrapnel. After examining the piece of metal from the IED Happy and Toby find a suspect. The team get the man to talk after fake “torturing” Toby and scaring the suspect into cracking. The man gives up Agent Taylor’s main Ghost suspect Javier Acosta who appears to be operating under a lot of pressure. Meanwhile, Dodd suffers a seizure due to the swelling of his brain.
Walter’s mood darkens, but Taylor wants to keep pushing the team. Paige disagrees with Taylor's methods and tells her she needs to let the team register their shock. However, instead if apologizing, Taylor manipulates Walter and tells him that she has been chasing the Ghosts for seven years after they crippled her partner. Afterward, Toby and Walter settle their issues and move ahead. The team work out that the Ghosts are targeting a drug lord who double crossed the criminals in the past. As the team heads out, the Ghost gang attacks an armored truck, killing the guards and stealing a safe deposit box. Agent Gallo and team Scorpion get there after Javier and his team, who robbed the truck mounted on motorcycles and escaped. However, they chase them down. Walter gets close enough to confront one of the riders who knocks him down, but not before O’Brien plants his cell phone on the biker.
They use the GPS on Walter's phone to cut them off at the opening of an aqueduct, and Happy knocks two of the bike riders over by breaking open a fire hydrant. The leader, Javier, is chased off a roof by Walter. As the Ghost leader tries to climb down, the ladder falls away and Acosta grabs the roof with one hand and asks Walter to help him. At first, O’Brien hesitates, but when he decides to help, it is too late and Javier falls to his death. Walter denies feeling guilty over what happened on the roof, but he later asks Sylvester if it was possible to save Javier. Sylvester told Walter that Javier's weight would have pulled him off the roof, but Walter still blames himself, saying that he didn't know that before he hesitated. Sylvester survives but now he is scared to work at Scorpion. He doesn't want to tell Walter, however, because he knows it would hurt Walter. Megan promises to help him get through his issues. Toby also buys Sylvester new comic books, finally repaying his friend.
Agent Taylor invites Walter out for a drink, and makes advances toward him, trying to kiss him, and then inviting him back to her hotel room. However, Walter feels completely uncomfortable and turns her down, breaking off the kiss. Drew and Paige appear to be mending a few bridges, but Paige also cuts her date short to return to the hospital. Walter and Paige join the rest of Scorpion to visit a sleeping Sylvester in hospital. Cabe offers to have Homeland cover the cost of the babysitter and gets up to let Paige and Walter sit next to each other. They smile at each other before reading some of Sylvester's comic books.
- Elyes Gabel as Walter O'Brien
- Katharine McPhee as Paige Dineen
- Robert Patrick as Cabe Gallo
- Eddie Kaye Thomas as Toby Curtis
- Jadyn Wong as Happy Quinn
- Ari Stidham as Sylvester Dodd