The Framework changed everyone, but perhaps no one more so than Fitz. The sweet, nerdy scientist has taken an evil turn in the Framework on “Marvel’s Agents of S.H.I.E.L.D.” Season 4. Fitz is second in command at Hydra, and he was last seen making sure Daisy was punished for her Inhuman DNA. In Season 4, episode 18, audiences will learn more about how changing one regret put Fitz in this position.

The synopsis for the next episode is not exactly detailed: “The truth behind Fitz’s turn could bring down all of S.H.I.E.L.D.”

“Agents of S.H.I.E.L.D.” has yet to hint at what Fitz’s biggest regret is. Aida only changed one thing for each team member. Considering he doesn’t appear to remember Jemma Simmons (Elizabeth Henstridge), that seems to hint that his regret was from well before his S.H.I.E.L.D. days.

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When episode 18 airs, he’ll still have both Daisy (Chloe Bennet) and Radcliffe (John Hannah) locked up. He won’t be the only one hurting former friends. The promo video for the episode, titled “No Regrets,” reveals that May (Ming-Na Wen) will go up against the Patriot (Jason O’Mara). However, she’ll have extra help. Hydra has developed a serum to make her strong. Mace even questions if she is Inhuman.

Meanwhile, it looks like Coulson (Clark Gregg) will be embracing the reality he can only partially remember. Photos from Season 4, episode 18 show him in black tactical gear, and it looks like he just knocked out a Hydra agent.

With Coulson and Mack (Henry Simons) officially joining the resistance, that leaves May and Fitz to save. As two Hydra higher ups, it’ll be difficult to convince them that they haven’t always had an allegiance to the evil organization.

“Marvel’s Agents of S.H.I.E.L.D.” Season 4, episode 18 airs Tuesday at 10 p.m. EDT on ABC.

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