The episodes conclude storylines from throughout the series, and set up new plotlines and mysteries for the next season, with several recurring guest stars making appearances, including Kyle MacLachlan, Henry Simmons, Dichen Lachman, Ruth Negga, and Blair Underwood.

Having experienced more visions of the future, Raina realizes her destiny is to ensure that Skye discovers the truth about her mother and becomes the Inhumans' new leader.

Jiaying brings a number of Terrigen crystals aboard the vessel, intending to unleash their contents upon the entire world, to cause the Terrigenesis of every dormant Inhuman, and eradicate the human race.

Cal admits that he believed if he could find Skye, he could make Jiaying the benevolent person she was before Daniel Whitehall mutilated her.

Hunter and May bring Morse back to the Playground and Simmons operates on her to save her life, before telling Fitz that she is ready to address their feelings for each other once the crisis is over.

Discovering an SOS has been sent out, Jiaying kills Oliver and several other agents with a Terrigen crystal to coerce Weaver into expanding the beacon, so that all of S.H.I.E.L.D.

Jiaying sends Gordon to release Terrigen mists into the Iliad's ventilation, to kill all humans on board, but Mack, Coulson and Fitz fight to stop him.

Jiaying has other Terrigen crystals loaded on a quinjet to spread the mists across Earth, and tries to drain Skye's life force when she tries to stop her.

and is put in charge of all alien artifacts by Coulson, while Morse withdraws from field duty to recover from her injuries, and May takes a leave of absence to try to resume her relationship with Andrew Garner.

"[2] Bell also discussed the end tag of the episode, where Simmons is consumed by the Kree Monolith weapon, saying "When we first started talking about the Monolith, we knew that it needed to present a threat and we needed to demonstrate some of that threat and the promise of more story, because — this is gonna shock you — we want more people to watch next year, because we like when people watch our show.

The idea of getting Fitz and Simmons — who had been one person — to become two whole people, come back together, agree to go on a date, and then have this happen, felt beautifully poetic and promises some really intriguing stories next season, which is really what it's all about.

"[3] In March 2015, Marvel revealed that main cast members Clark Gregg, Ming-Na Wen, Brett Dalton, Chloe Bennet, Iain De Caestecker, Elizabeth Henstridge, Nick Blood, and Adrianne Palicki would star as Phil Coulson, Melinda May, Grant Ward, Skye, Leo Fitz, Jemma Simmons, Lance Hunter, and Bobbi Morse, respectively.

[1] Simmons, Maclachlan, Harris, Adams, Stewart, Stojan, Lachman, Mitchell, and Vela-Bailey return for part two, where they are joined by Blair Underwood as Andrew Garner, Brendan Wayne as Jiaying's assistant, Robert Reinis as bartender, Daz Crawford as Kebo, and Anthony D. Washington as TAC agent #3.

Mattocks, Powers, Vela-Bailey, Wayne, Reinis, Crawford, and Washington did not receive guest star credit in the episode.

Simmons, Negga, MacLachlan, Harris, Adams, Stewart, Stojan, Lachman, Mitchell, and Vela-Bailey reprise their roles from earlier in the series.

[3] Expanding on that last shot with Simmons, visual effects supervisor Mark Kolpack explained that Henstridge was dragged away from camera on a small sled, with Houdini FX used to simulate the liquid weapon around her.

The different artists were once again chosen to create the teaser posters, based on their previous work and how it connected to the themes and emotion of the intended episode.

[12] For "Part 2", artist Joshua Budich brought together all of the main players of the season, divided into Coulson and his team, and those who served as antagonists to them throughout the season (though not necessarily villains), with Skye and some Terrigen crystals in the middle, pointing to Skye's confused allegiances and the importance of the crystals in the finale.