Last week on Supergirl, The CW series revealed the full scope of Lex Luthor's plans, revealing along the way how he's manipulated every step to get to a point where he is going to use Leviathan to destroy Supergirl and then destroy Leviathan himself so that he can control the world. His plans move forward a bit this week as he makes a final play to earn the trust of Leviathan, but Supergirl isn't going to make things easy for him. She's determined to stop both Lex and Leviathan, especially when Rama Khan returns. Meanwhile, issues with Non Nocere present their own complications as well. As the last episode before the season finale, there's a lot going on in "The Missing Link". Read on for our spoiler filled recap below.
Spoilers for Supergirl's "The Missing Link" below.
The episode opens with yoga in a prison with the leader reminding everyone to praise Lena Luthor for giving them the peace they've been enjoying as they were the test subjects for Project Non Nocere. However, when the elevator goes out due to the solar event, aka the Sun Eater, one of the inmates freaks completely out.
At the DEO, Brainy confronts Lex about that Sun Eater, accusing him of working with Leviathan rather than against them. Lex pressures Brainy to "trust the process" even if that means letting his friends die. At the Tower, the heroes can find no trace of Leviathan and Supergirl is convinced that Lena is somehow involved with the dangerous group.
Lena and Lex go to the prison to check on the inmate. Obsidian announces their Worldwide Unity Festival, but Kelly and William have deep concerns. Alex reaches out to Kelly's friend, Pete Andrews -- the real one -- for help trying to find Leviathan. At the Leviathan headquarters, Gemma shows Rama Khan a weapon that Lex stole from the Fortress and tells him to get what she needs to make it work and destroy the supers.
Lena figures out that the issue with the prisoner is that his natural survival instinct essentially overrode Non Nocere and now it’s entirely messed up. Elsewhere in the prison, the inmate who was attacked also freaks out and turns violent and attacks another inmate. It leads to everyone freaking out and a full-on riot.
Dreamer has a dream that leads her to where Rama Khan is and they alert Supergirl, soon enough, Team Supergirl heads to Oregon where Rama Khan is trying to cause a major earthquake. Brainy sends DEO backup. Supergirl and Dreamer go up against Rama Khan but manage to get his staff away from him and defeat him. Brainy arrives to take Rama Khan, though Supergirl warns him that she thinks Lex is working with Leviathan. Dreamer tells Supergirl that Brainy was in her dream, using Rama Khan.
As Brainy questions Rama Khan, Dreamer realizes the whole things was a trap. Brainy realizes the same and Rama Khan breaks free his restraints. Despite the best efforts of Supergirl, Rama Khan collects all the kryptonite at the DEO. J'onn and M'gann show up and save Dreamer, Supergirl, and Brainy, but Rama Khan escapes with the kryptonite and levels the DEO.
Lena is able to reset Non Nocere, but the reset doesn't really work. It just sets people back to normal. She realizes that Non Nocere is dead and Lex tells her that mankind can't be fixed; it can only be controlled. Lena realizes Lex has been manipulating her from the start, again.
After Alex and Pete are attacked trying to get information about Leviathan, Alex returns home to Kelly and talks about the situation. Kelly suggests that if Alex is going to operate as a vigilante, she should really start wearing a mask.
William notices that the video of Margo included the use of an image inducer which ultimately leads him and Kelly to discover that it was Eve Tessmacher. William tries to track down Eve only to end up kidnapped himself.
Lex has the prison burned down with the prisoners in it to cover his tracks and then gets an invitation to the Leviathan ship. Lena goes to Kara's apartment and apologizes. She tells Kara that Lex is working with Leviathan and that she wants to help stop them. Kara tells her to sit down.
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