"Cliffhanger" is the twenty-first episode of the first season of Scorpion. It aired April 13, 2015.
Walter learns Cabe's long-hidden secret regarding the Baghdad mission and it threatens to tear Team Scorpion apart. Meanwhile, Ralph puts his life in danger to help the team.
At the Campbell Neurotoxicity Laboratory, Jim Stone got locked inside a room in which sarin gas was released, and whose suit’s oxygen levels were dangerously low, much to the dismay of fiancé, Sarah Jacobs.
At the Scorpion office, Toby made Paige realize that Ralph, who had dressed up in a suit and tie for picture day, was emulating Walter. He showed Ralph the engine of the Ferrari that he had just gotten as a gift from technological billionaire Richard Elia. Before Ralph left for school, Walter reassured Ralph that he was an important member of the team.
Meanwhile, the Scorpion team was called in to help out with the situation at the Neurotoxicity Laboratory. The perpetrator demanded that the government release all of the files related to the Baghdad bombing fiasco 16 years ago, which included Walter’s involvement in it. The perpetrator then gave them a deadline of ninety minute. It was until he filled the entire facility with nerve gas, which he could do as he had complete control of the facility’s system.
However, as they ran out of time, the perpetrator cut of Jim’s oxygen supply. He died after removing his helmet, which caused him to take in all of the sarin gas in the room. They were then they were given sixty minutes to comply.
Walter then realized that they couldn’t get into the system because the problem was internal. It meant that they had to get inside to repair whatever had been broken, so that Sylvester could gain control of the entire system.
Cabe then pulled Walter aside and finally told him the entire truth about Baghdad. He had known three days before the mission commenced that Walter’s system was going to be used to bomb an Iraqi leader, and not for humanitarian aid like he said. He had done this because he knew that Walter would have compromised the system.
They then got Sarah to go to the main server, which showed them that the main cables had been cut. As Sarah began to panic, Cabe tried to calm her down. After hearing Cabe trying to get Sarah to trust him, Walter yelled at him to "shut up". He told Director Merrick that after this particular case, Scorpion would no longer work with Cabe. Because of this, Cabe resigned and waited outside. Paige then tried to smooth things over to no avail.
They then discovered that Dr. Simon Boyd, the scientist in control of the toxin storage, was the perpetrator. He was looking for revenge against the government as his fiancé, who had just died, had been paralyzed by the bombing, as she had been there at the time. Walter then decided to go on using fire resistant suits, and Paige convinced him that Cabe go with him. They then began to go down by using magnets, but Cabe began to slip after the incinerator chute turned on again. However, Walter managed to save Cabe by pulling him up into the crawlspace in the vents, as he had managed to slice through the chute sideways.
Walter then began to patch up the cables and got Simon’s attention so that Cabe could evacuate the building. However, after Simon realized that he had been tricked, he held Walter at gunpoint and began to release the gas into the different zones in the building. However, he managed to quickly slice the cables and got out of the building locking Simon inside, who then dies, much to Walter's dismay.
Ralph, who had escaped from the principal’s office at school, distracted the guards, and started to go down the chute, which Sylvester had turned off for him, in order to patch up the hole that Walter had created so that the gas wouldn’t leak out from there, which would endanger the entire city. Happy, Toby and Paige managed to pull Ralph out just in time before the fire in the incinerator burned him, as the entire facility had reset.
Back at the office, the other members of the team, who thought that Cabe leaving was a bad idea, couldn’t seem to talk to Walter at all. Paige then told Walter that she was leaving with Drew and Ralph to Maine. It was because being near Walter was becoming too dangerous for Ralph.
Upset, Walter drove the Ferrari above the normal speed limit and crashed into the railing down a cliff after he avoided hitting a coyote.
- 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