A terrorist group called the "Watchdogs" attacks the A.T.C.U. with Howard Stark's technology imploding the building, leaving nothing but a ball of rubble, causing Daisy to take action against this group that she's hated.
The group is anti-alien, standing for everything Daisy wants to fix in society. When an ex-S.H.I.E.L.D. agent is believed to be leading the group after their upgrade from online hate comments to bombs, the team digs deeper to put a stop to these terrorist attacks.
Mack's family life is explored as he and his brother deal with their multiple issues over his hidden job that takes him away for months at a time. But things are only complicated by Bobbi and Hunter's departure, which clearly effects Mack.
His absence is his family's life causes a strain between them and Mack, because he's unable to divulge any details about his job. They think he's an eccentric insurance agent, who is always traveling and always has a "thing."
Meanwhile, Jemma finally deals with her guilt and vulnerability after being trapped on the alien planet and letting Lash free. May helps her, as she starts to take up methods to protect herself.
But May also needs help. She's been tracking Lash, in order to take him out, for good. She wants to save him from himself.
Fitz and Daisy pair up on the mission to stop the Watchdogs, but Daisy's recklessness causes immediate harm to Fitz. He's shot by the imploding bomb and Daisy has to figure out how to get it out before things get messy.
Lincoln returns from his S.H.I.E.L.D. evaluation, but Coulson isn't happy with him, so he brings him along on a mission to test him.