D'aja Vu is the sixth episode of 3Below.
A giant troll wreaks havoc at the school science fair, threatening to expose both the troll world--and the royals true identities.
Eli is riding his bike when he gets distracted seeing Aja and Krel's ship crash. A piece breaks off and lands in the forest. Time passes.
Jim, Blinky, Claire, Toby, and AAARRRGGHH!!! run from a Troll, Porgon, a trickster. Porgon trips over the debris from the ship and picks it up. It starts flashing and then Porgon disappears.
Aja's alarm wakes her up. She goes out to find the blankbots making pancakes. Krel reminds her of the science fair. She forgot because it's her first day of training with Varvatos. The first skill she must learn is patience. Krel is more focused on his science experiment. He wants to win the fair. Varvatos says Aja's next lesson is to help Krel.
Aja and Krel bring in his science project. All the other students have done volcanos. He brought a piece of the daxial array with him. He thinks he'll be meeting his intellectual equals in the judges. Instead, Lawrence and Janeth are the judges. Aja leaves to go home to train. On her way out, she runs into Jim, who is looking for Porgon.
Lawrence announces that Steve is the winner, for his traffic cone volcano. Porgon then drops in from above. Aja thinks it's another bounty hunter. Porgon takes Krel's project. Jim steps in to activate his amulet to protect him from a planet Porgon threw, but Aja steps in front of him and uses her shield to protect them both. Claire and Toby then work together to attack him from above.
Aja wakes up to her alarm again. She quickly realizes she's back at the morning she already lived. No one else knows.
Aja notices that everything is happening just as it did before. She leaves Krel alone to go find answers and gets pulled aside by Jim. Jim says he needs Aja's help. Porgon then appears. Aja recognizes the object he's holding as Akiridion. Porgon attacks again just as before and Aja finds herself reset again.
Aja tells Krel not to go to the science fair. She wants them all to sit and be patient. Krel refuses to stay at home. Aja notes the same things happening yet again. She finds Jim at the same place as before. He thinks the repeating days are due to Porgon. He's been through the day 30 times. Aja asks him what she has to do to save everybody like he said she could. Jim says they'll time loop again and asks her to tell him what Akiridion tech is. She explains that it's from her home planet and shows him her true form. They both activate their shields again and time loops again.
Jim wakes up to find Aja by his bedside in her alien form. She's there to help him, but he needs backup.
Krel, Aja, Jim, Claire, and Toby meet in the woods and talk about Porgon. Blinky and AAARRRGGHH!!! then appear. Varvatos, who has been watching secretly, sees them and attacks, thinking they're bounty hunters. He and AAARRRGGHH!!! fight each other for a moment before Krel and Aja say he's good. They hear Porgon at the Planetarium. Aja uses her shield to protect all of them from the reset.
The whole group is at Aja and Krel's house in the morning. They're all fascinated. Aja says they need to unloop time now. The device Porgon has is to recycle energy, not time. But they believe he is using his troll magic to loop time. Krel remembers that Porgon keeps going after the piece of the Daxial Array. He could use it to destroy time itself. They have to destroy the device before he can use it again. Jim says they have to be careful because as soon as he feels threatened, Porgon will send them back to the morning again.
Aja attacks Porgon and tries to get the device, but he just resets time again.
Jim stops Aja from leaving again. He tells her about his experience in the Darklands when he went alone. She explains why she can't be patient.
They work together to execute their plan. At the science fair, they all plant green stones on the volcanos. Porgon attacks again and Blinky activates all the stones so set off the volcanos simultaneously. That gives them the distraction they need to separate him from the object, then Jim and Aja work together to defeat him. Mary and other students take pictures of the trolls. The police come in and order them to put their hands up. Krel has an idea of how to activate the time loop one last time, destroying the Dekyon Charger in the process. That means today will never happen, which means they won't have become friends. Blinky is confident that they'll meet again. They activate the device one last time.
Porgon runs through the woods. He comes across the Dekyon charger, but it disappears and Jim is able to defeat him.
Steve is declared the science fair winner. Krel is disappointed not to have won. As Aja talks to him, she backs up accidentally into Jim.
- Tatiana Maslany as Aja Tarron
- Diego Luna as Krel Tarron
- Nick Offerman as Varvatos Vex
- Glenn Close as Mothership
- Ike Amadi as Detective Scott
- Kelsey Grammer as Blinky
- Cheryl Hines as Momblank
- Emile Hirsch as Jim Lake Jr.
- Tom Kenny as Dadblank/Officer Brennan
- Lexi Medrano as Claire Nuñez
- Laraine Newman as Miss Janeth
- Cole Sand as Eli Pepperjack
- Charlie Saxton as Toby Domzalski
- Fred Tatasciore as AAARRRGGHH!!!
- Brook Chalmers as Porgon
- Lauren Tom as Mary Wang
- Frank Welker as Luug
- Thomas F. Wilson as Coach Lawrence
- Bebe Wood as Shannon
- Steven Yeun as Steve Palchuk
- This is the first episode of 3Below to feature the main cast of Trollhunters together (Jim, Toby, Claire, Blinky, and AAARRRGGHH!!!)
- At the conclusion of this episode, Aja is heard saying terms such as 'awesomesauce' which are associated with Trollhunters. This is possible to be an aftereffect that outlasts the time 'reset'. The full extent of this is yet to be clear.
- Goof: This episode cannot logically take place during the Trollhunters Part Three timeline because both Claire and AAARRRGGHH!!! are present, even though when Claire was no longer possessed by Morgana, AAARRRGGHH!!! was taken captive by Gunmar.
- Plausibility: However, it could be most likely that it takes place before "So I'm Dating a Sorceress", as (if viewed closely) Claire's eyes look red from sickness, but is effectively getting better.
- Title: The episode's title is in reference to the French term Déjà vu (translation: "Already seen"), describing the feeling that one has lived through the present situation before.
- Running Gag: Shannon's volcano always breaks when she runs into someone (Aja, Porgon, Toby, and Steve).
- The song that continuously plays on Aja and Jim's alarm clocks is "Easy Peasy" by The Kinnardlys.
- Continuity: Jim's legs being (unusually) skinny are once again referenced, this time by Krel when he exclaims "Wait, wait, wait, wait, I'm supposed to believe this peculiarly skinny-legged human when he says the space-time continuum has been altered, trapping us in the same mono-chronic cyclone." That last time they were mentioned was in the Trollhunters episode "Hero with a Thousand Faces".