Inescapable is the sixth episode of the sixth season of the television series Agents of S.H.I.E.L.D..
They've fought through space, time and alternate realities to find each other, and now, closer than ever, only their own demons can stop FitzSimmons' reunion.
Despite Enoch warning her against it, Atarah puts Leo Fitz and Jemma Simmons into a Cerebral Fusion Machine. In the simulation, she describes to them the Destruction of Chronyca-2 and explains that she wants to travel in the past to avert it, meaning that Fitz and Simmons have to figure out a way to perform a time travel. Atarah explains that all of Fitz's and Simmons' memories will be accessible and shareable, both to each other and to herself, which upsets Simmons.
Before getting to work, once they remain alone, Fitz proposes to Simmons in a similar way than his other counterpart already did, and Simmons accepts. They then discuss the places where they have been recently in their recent quests, but Fitz notices that Simmons does not want to talk about what happened in 2091. Fitz presses on the issue, which causes Simmons to regress into a child version of herself, who runs into her bedroom. Fitz finds her, and begins to fear that their minds could become their prison.
Fitz eventually manages to have Simmons return into her adult self by pretending he will seek assistance from Aida. However, Simmons is unable to contain the memories she wants to keep Fitz unaware of: that another version of Fitz died in the Battle of Chicago, that they already had a wedding, and that Phil Coulson has died as well. This is too much to bear for Fitz, who leaves. Simmons finds him in a reconstruction of his room at the S.H.I.E.L.D. Academy, and tells him that she knows about Fitz still being traumatized by what happened in the Framework.
Fitz and Simmons realize that since they are trapped in their minds, then The Doctor is present as well. They are soon confronted by Fitz's dark side, and when they run away from him, they find themselves back into Simmons' child bedroom. However, the music box in which Simmons used to pretend she put all her troubles in accidentally opens, releasing Id Simmons, a horrific version of Simmons comprised of all of Simmons' fears and pains. Fitz and Simmons hide from her in a closet, and are transported in the Lighthouse as it is now used by S.H.I.E.L.D.
Fitz decides to take Simmons and himself to the moment which started their path of pain: the day they accepted to join Coulson's Team. As they relive this memory, however, Fitz is attacked by Id Simmons, which causes him to be captured by the nightmarish creature in the Zephyr One, while Simmons is also captured by The Doctor. Both are submitted to brutal torture, but Fitz and Simmons eventually figure out that they were never alone in this: they have their friends. This causes simulated versions of Alphonso Mackenzie and Quake to appear and respectively rescue Fitz and Simmons.
Fleeing from their attackers, Fitz and Simmons find themselves trapped in a Containment Module. A violent argument then erupts between the two, as they blame each other for all the pain they have suffered for years. Fitz notably brings up his brain injury, as well as Simmons being taken to Maveth and falling in love with Will Daniels, while Simmons counters by recalling all the pain Aida and the Framework, the creation of both having Fitz's involvement, have caused.
The argument escalates further, with Fitz claiming that despite all appearances, Simmons is as damaged as he is. When Simmons recalls Fitz saving her from the bottom of the ocean, water begins to break into the module, threatening to drown them. Panicking, Fitz and Simmons keep yelling at each other, but this ultimately leads them to confess once again how much they love each other and how they are willing to die for one another. This miraculously causes the water to stop.
Having reconciled, Fitz and Simmons decide to face their shadow selves together. However, once they are out of the containment pod, they find The Doctor and Id Simmons passionately making out: their dark sides are as compatible as the real Fitz and Simmons are. Fitz and Simmons are brought back in the initial stage of the simulation, and as they agree to marry once again, Atarah reappears, informing them that they have lost five minutes of their time.
Fitz and Simmons decide to refuse to work for Atarah, as they are willing to remain imprisoned as long as they are together. Atarah tries to explain that they will not be together, but she suddenly collapses while Fitz and Simmons are taken out of the Cerebral Fusion Machine. Indeed, Enoch has boldly knocked unconscious all the Chronicoms and helps Fitz and Simmons escape thanks to an Inter-Planetary Conveyance Disc.
Meanwhile, at the Lighthouse, Alphonso Mackenzie informs Quake of the destruction of Chronyca-2, and voices his suspicions that Sarge's Squad, who they have captured, is responsible for it.