"Devils You Know" is the fourth episode of the third season of Agents of S.H.I.E.L.D..
Having reluctantly agreed to share information with Rosalind and the ATCU, Coulson and the team go in search for the Inhuman who is killing off other Inhumans, and May feels that Hunter’s mission to take down Ward is getting too personal.
S.H.I.E.L.D. tries to recruit two Inhumans who left Afterlife with Alisha's help, but Lash that's been killing Inhumans bursts into their apartment and kills the couple. Alisha, who is still on the plane with Coulson, feels her duplicate's death and goes into shock. Coulson orders Mack and Daisy go in after the killer, but he's already gone. They hurry after him while Coulson, Bobbi and Fitz calm down their neighbors and investigate the scene. In the apartment, Bobbi found some hairs Lash left behind. Although Lash is already gone, Daisy and Mack come face to face with the ATCU, but Rosalind prevents this from escalating into a shoot-out. Back at the scene, Rosalind and the ATCU take the bodies of the two dead Inhumans. Meanwhile, Ward and Kebo are over looking a crate full of weapons that Hunter offered them. Ward discussed his plans for the new HYDRA, noting key comparisons between his vision and S.H.I.E.L.D.'s values, claiming he almost viewed it as a shame that he was going to destroy it. Hunter tells May he final getting closer to Ward. May warn him to be careful.
At the Playground, Bobbi discovers the killer is himself an Inhuman. Daisy, discovers the killer has been tracking his victims using a virus embedded in an email. Daisy and Coulson discussed working with the ATCU. While Dr. Garner asked Jemma about her time on the alien world. After Andrew talks to Coulson about Alisha, his other patient, May arrives back at the Playground. May let Hunter go on his own, she afraid Hunter is over his head and asked Coulson for back up. However for the time being to get inside Ward's base, Hunter will let May know when it's time to strike. With the information she brings him. At the Lab Fitz and Bobbi studying Lash's DNA but Fitz pick up Simmons' research on the Monolith. Simmons than walks in and shout at Fitz than walk off. Then Daisy found tracked the virus to Dwight Frye, a former I.T. guy living in Baltimore who Daisy suspects might have been the killer before he changed. In Baltimore, Coulson, Daisy and Mack meet with the ATCU outside of Frye's building. They go in together expecting a fight, but Daisy finds Dwight cowering in a closet. He tries to force her out, but Daisy uses her powers to throw him back into the closet. S.H.I.E.L.D. and the ATCU surround him, and they realize Daisy is what's setting him off. The other agents leave Coulson and Rosalind alone with him. Frye reveals that ever since he's changed, being in the presence of other Inhumans gives him migraines and other painful symptoms. Lash, the Inhuman killer, contacted Dwight with a list of other Inhumans tortured by their powers, and told him that if he could find them for him he would put them out of their misery.
The ATCU takes Dwight into their custody. Coulson wants Mack to go with them and check out the ATCU's facilities, but Daisy insists she goes with them as well. Coulson asks Rosalind to let them go with her, and after talking with Banks she agrees. Back at the Playground, Bobbi is working out when Jenna and asked that did she tells Fitz that she want go back to the alien planet. bobbi that said no and tells Jemma she is worry about hunter. Elsewhere Hunter gets pick up by Kebo and another HYDRA agent to see Ward, who's now calling himself "the Director," but Hunter has to ride in the trunk of the car the whole way. While en route to the ATCU's base, Lash attacks the transport. He cuts his way into the trailer and takes out the ATCU's guards. Daisy tries to stop him with her powers, but it causes the truck to over. Lash drags Dwight from the wreck. Frightened, Frye begs for his life, telling the monster that he only told them the truth about him, and that he's merciful. Lash responds that he isn't merciful but necessary, and kills Frye. Daisy and Mack, meanwhile, are pinned down in the wreck, and Daisy sees Lash's shadow take the shape of a human as he leaves. Daisy later tells Mack what she saw while they recover in the ATCU's hospital.
Back at the Playgound, Coulson take a team to go after Ward. Hunter arrive at a HYDRA base, Hunter finds out that Ward is styling his new HYDRA after S.H.I.E.L.D. When he questions this, Kebo says he can ask the director himself, as Ward is standing right behind him. Hunter grabs a nearby machine gun and reveals himself. Ward is disappointed that only Hunter and especially not Bobbi would go after him when his men tell him there are no S.H.I.E.L.D. reinforcements surrounding them. Hunter is surrounded by Hydra agents, but Agent May intervenes. Just as they pin Ward down in his office, Ward throws a phone between them. The phone shows a live video feed of Dr. Garner. Ward warns them that his men will kill him soon, but Ward promises them that he'll call them off if they put their weapons down and leave. Werner and a team of HYDRA thugs, meanwhile, surrounds Dr. Garner in a convenience store. Hunter calls Ward's bluff, and opens fire into the office. Kebo smashes a window and he and Ward escape in the back of a truck, but as Ward leaped through the window one of Hunter's bullets hits his back. May, worried for her ex-husband's safety, calls Andrew, but gets no response. Back at the convenience store, Dr. Garner's phone is on the ground near Andrew body. Gasoline has spilled all over the store's floor. Werner ignites the gas and runs out of the store just before the explosion. Something, however, has Werner terrified.
Back at the Playground, Fitz confronts her about her research, but Simmons tells him she needs his help to get her back to wherever the Monolith took her. Something happened to her over there, and she's ready to tell Fitz about her ordeal.
- Clark Gregg as Phil Coulson
- Ming-Na Wen as Melinda May
- Brett Dalton as Grant Ward
- Chloe Bennet as Daisy Johnson/Quake
- 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
- Luke Mitchell as Lincoln Campbell
- Matthew Willig as Lash
- Blair Underwood as Andrew Garner
- Constance Zimmer as Rosalind Price
- Daz Crawford as Kebo
- Andrew Howard as Luther Banks
- Spencer Treat Clark as Werner von Strucker
- Alicia Vela-Bailey as Alisha
- Alexi Wasser as Lori Henson
- Nick Eversman as Shane Henson
- Chad Lindberg as Dwight Frye
Continuity and References to the Marvel Cinematic Universe
- Joey Gutierrez is mentioned.
- Spud is mentioned.
- Kara Palamas/Agent 33 is mentioned.
- Terrigen Mist is mentioned.
- S.H.I.E.L.D. Helicarrier is mentioned.
- Kebo says that Ward is considering calling their base Omega Point. Omega Point was a HYDRA Base in the Secret Warriors comic.
- "Dwight Frye" is the same name as the actor who played Renfield in the original Dracula film.