"Who You Really Are" is the twelfth episode of the second season of Agents of S.H.I.E.L.D..
Coulson and team come to the aid of a confused Lady Sif, who has lost her memory after fighting with a mysterious warrior whose true mission will send shockwaves through S.H.I.E.L.D. Meanwhile, Bobbi and Mack continue to hide their true mission from everyone close to them
Lady Sif, dressed in human clothes, washes ashore on a Portuguese beach. She approaches three people camping out on the beach. She is completely unintelligible to them, only rambling on about someone named "Kava." When one of the three tries to help her, she pushes him away with her Asgardians strength.
At the Playground, Fitz interrupts a training session between May and Skye. He's concerned about how Skye has changed since her transformation, but she reassures him she's doing fine before May scares him off. Meanwhile, Coulson tells Mack he wants to promote him to a field agent to make better use of his imposing appearance. Agent May then informs the Director that they've received a message from one of their contacts in Portugal saying they have Lady Sif in their custody. The whole team flies to Portugal to look into her reason for being on Earth. Unfortunately, she has no memory of why she is on Earth, why she is in human clothing, or who she is at all. Although this appears to be a dead end, Skye finds a video on Twitter of Sif fighting on a dock with a strange man they believe to be the "Kava" she is looking for. Bobbi and Skye go to a nearby hospital to see if the man is being treated there while the rest of the team goes to the dock to look for any clues as to his identity. Simmons runs an analysis on a tissue sample from Kava, but discovers it is in fact liquid nitrogen; however, no one knows why the man might have needed liquid nitrogen. At the hospital, Bobbi and Skye find Kava, who is now completely blue-skinned, using liquid nitrogen to change the color of his skin to that of a Caucasian human's. He attacks the two of them, but before Skye can fire a shot she starts generating tremors that rip apart her gun and allow Kava to get away.
The team regroups on the Bus. Now that they know the man is a Kree, Sif realizes "Kava" is not his name but is the Kree word for "Keys." They see he is headed towards a Portuguese city called "Chaves," the same place where Daniel Whitehall found the SSR, and they corner him while he is leaving a cave while dragging a large crate. S.H.I.E.L.D. takes the Kree into their custody and begin questioning him aboard the plane. He reveals his name is Vin-Tak and claims he is there to help. He also says he only took Sif's memory away from her so she would stop tracking him, and that he could restore it if he could have access to his truncheon. Coulson gives him the opportunity to prove he is friendly once they get back to the Playground. However, the Vin-Tak kicks his truncheon out of Coulson's hands and jabs Sif with it, but suddenly drops it and holds his hands up. Sif recovers with her memories in tact. She reveals Odin sent her to Earth when Heimdall saw a Kree arrived on Earth. Vin-Tak, however, says he came to Earth because he received an ancient signal indicating that someone on the planet had underwent Terrigenesis. He goes on to explain that a faction of his people came to Earth thousands of years ago to genetically modify early humans into becoming their weapons. The modifications would be activated if they came into contact with Terrigen crystals, which were stored inside the Diviners. However, the modified humans proved to be too powerful, so the other Kree came to Earth and shut the project down, but left behind a collection of Terrigen crystals large enough to create an army.
At this time, Simmons, who was studying the crate with Fitz, discovers it is completely empty, and lets Coulson know of her find. Vin-Tak says his worst fears have come true, and they must find the remaining Diviners and anyone else they transformed. Coulson tells Sif and Vin-Tak that Skye was there when Raina transformed. They start asking her questions about what she saw, but she gets uncomfortable when Vin-Tak says the transformations are not always physical. The room starts shaking, and they realize that Skye was indeed transformed like Raina. Vin-Tak and Sif want to take her with them and put her down, but Coulson refuses to hand her over. May runs away with Skye and hides in the Playground's jail cell. The two aliens overpower Coulson and chase after them. Bobbi distracts the Kree away from Skye, and lures him into a trap where Fitz shoots him with one of S.H.I.E.L.D. experimental rifles before she takes away his memory with his truncheon. Sif, however, catches up to May and Skye, and attempts to break into the cell. May tries to get Skye to control her emotions, but with no success. Once Sif gets through the wall separating them, Skye grabs May's I.C.E.R. and knocks herself out, stopping the tremors.
The next day, Sif and Vin-Tak, whose memories are slowly coming back to him, take the Bifrost back to Asgard, where the Asgardians will make sure he returns to the Kree homeplanet of Hala. Back at the playground, Simmons, Mack, Bobbi and Hunter confront Fitz about hiding Skye's transformation from the rest of them. Skye defends his and Skye's decision not to come forward, citing Simmons' calling the transformation a "plague that needed to be eradicated," and how they should be protecting Skye. Mack argues back that really it's them that all need to be protected from her, a statement Skye overhears him say. Since the team no longer trusts her, Skye locks herself inside the isolation unit on the Bus. Some time later, Hunter confronts Mack about the secret he and Bobbi are hiding from the rest of the team, but Mack puts Hunter in a sleeper hold that knocks him out.
- Clark Gregg as Phil Coulson
- Ming-Na Wen as Melinda May
- Brett Dalton as Grant Ward
- Chloe Bennet as Skye
- Iain De Caestecker as Leo Fitz
- Elizabeth Henstridge as Jemma Simmons
- Nick Blood as Lance Hunter
- Adrianne Palicki as Bobbi Morse
- Henry Simmons as Alphonso "Mack" Mackenzie
- Jaimie Alexander as Sif
- Eddie McClintock as Vin-Tak
- Alexandra Manea as Nurse
- Lidia Porto as Head Nurse
- Danny Lopes as Bruno
- Ben Griesse as Tiago
- Ruben Rabasa as Mr. Cardozo
- Markell Andrew as Officer Carvalho
Continuity and References to the Marvel Cinematic Universe
- Lady Sif appears.
- Asgard is mentioned.
- Lorelei is indirectly mentioned.
- Raina is mentioned.
- I.C.E.R. appears.
- Thor is mentioned.
- Odin is mentioned.
- A Kree appears.
- HYDRA is mentioned.
- Daniel Whitehall is mentioned.
- Strategic Scientific Reserve is mentioned.
- Terrigenesis is mentioned.
- Antoine Triplett is mentioned.
- Diviner is mentioned.
- Heimdall is mentioned.
- Richard Lumley is mentioned.
- Grant Ward is mentioned.
- The Kree-Nova War is mentioned.
- Terrigen Crystals is mentioned.
- Kree City is mentioned.
- Coulson's Revenge appears.
- Hala is mentioned.
- Bifrost is mentioned.
- Roxann Dawson previously directed the season one episode Eye-Spy.
- Vin-tak is the same species as Ronan from Guardians of the Galaxy.
- Coulson's huge gun, used to shoot Loki in "The Avengers" and used in this episode to subdue the Kree Vin-Tak, is named "Bambino".
- Eddie McClintock's voice was digitally altered for his role.
- Lady Sif from Thor and Thor: The Dark World makes her second appearance in the series.
- Billy Boyd who played Pippin in The Lord of the Rings trilogy, makes a brief cameo at the beginning. He is in the background holding a guitar on the beach.