Devils You Know is the fourth episode of the third season of the television series Agents of S.H.I.E.L.D. and the forty-eighth episode overall.
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.
Alisha Whitley goes to S.H.I.E.L.D. and sends a clone on a recruitment assignment for a married couple of Inhumans she knew from Afterlife. The couple is killed by Lash; Lash also kills the clone, causing Alisha to lose control of her powers temporarily. Daisy Johnson and Alphonso Mackenzie chase Lash, but only run into the Advanced Threat Containment Unit, their partners, as per the agreement Phil Coulson and Rosalind Price established.
Before she died, Lori Henson told Alisha about an e-mail she received saying that Inhumans should assemble. Researching the e-mail, Johnson discovers Dwight Frye, an Inhuman with the power of detection who not only hates himself but all of his kind. He gave Lash intel on how to find Inhumans to kill. As the ATCU took Frye into custody, Coulson insists that Johnson and Mackenzie accompany them to their facility; this causes Luther Banks to abruptly leave.
En route to the facility, Lash attacks and kills Frye. Johnson, too injured to help, notices though that Lash has a second, human form as he transforms and escapes.
Jemma Simmons has spent the past week researching the Monolith. When Leo Fitz discovers her research, she takes it from him, telling him to leave her things alone. Bobbi Morse assures Simmons that she has told no one that Simmons wishes to return to the other planet. When Andrew Garner interviews Simmons, she gives him very little information.
Meanwhile, Lance Hunter is given an assignment by Kebo; Hunter has no idea what it is, to the dismay of Melinda May. May informs Coulson that she is working with Hunter. Coulson tells May that he needs her with him and that if his working with Garner has upset her, that can be terminated. May refuses, citing that Hunter needs her more right now and that Garner is good at his job. Garner and May have a brief conversation, but her concerns are about Hunter.
At the assigned time, Kebo introduces Hunter to the "Director" of HYDRA. Grant Ward is surprised and a firefight begins. While the men exchange quips about Agent 33 and Bobbi Morse, May arrives as back-up, though Coulson is too far away for immediate assistance. Ward reveals that Werner von Strucker is stalking Garner; if Hunter allows Ward to escape, von Strucker will not kill May's ex-husband. Hunter, over May's protests, does not accept the deal and continues his attack. Von Strucker and two other operatives surround Garner.
At the Playground, Simmons tells Fitz that she will give him full disclosure about what happened to her on the other planet.
During the firefight, Kebo helps Ward to escape; Ward takes a shot in his back as he flees.
Von Strucker escapes as the building where he fought Garner explodes.