In the S.H.I.E.L.D. Lab, Coulson tells May that this world is a simulation meant to keep them prisoners, but May isn't having any of it. She tells him that she's not going to follow blindly anymore: Not Hydra, not him. So if he wants her to believe him, he'll have to show her proof. Watch this sneak peek from Marvel's Agents of S.H.I.E.L.D. Season 4, Episode 20: Farewell, Cruel World! airing TUESDAY 10|9c on ABC.