- "This is the last day."
- ―Robin Hinton
After crashing the Trawler on the surface of the Earth, Phil Coulson, Daisy Johnson, Leo Fitz, Jemma Simmons and Deke Shaw are rescued by the True Believers, who take them to the remnants of the Zephyr One which have survived the cataclysm of the destruction of the Earth. They are greeted by Samuel Voss who tells Shaw that his father is on his way back to the Zephyr One. The S.H.I.E.L.D. team unsucessfully tries to get answers from Robin Hinton, who is still lost between times and can only tell them ominous enigmas. Flashbacks show that following the death of her mother, Hinton was taken to the Lighthouse and was raised by May. Other S.H.I.E.L.D. agents were also present at the Lighthouse: Leo Fitz and Jemma Simmons unsuccessfully worked on a way to prevent the global disaster and Yo-Yo Rodriguez rebelled against the Kree Watch when they sought to take control of the Lighthouse.
Johnson and Shaw have a conversation about their respective fathers and Johnson tells Shaw that he should not worry about his impending reunion with Owen. Fitz and Simmons discover a strange mechanism in the Zephyr One and Voss explains that it was built by Owen to bring the S.H.I.E.L.D. agents from the past. Later, Coulson and May discover that the True Believers have a fragment of the Time Di'Alla which fits into the mechanism discovered by Fitz and Simmons. However, Shaw is visibly troubled by the fragment. He confronts Voss about it, claiming that it belonged to his father and that Owen would never have left it far from him. In response, Voss punches Shaw and locks him away, and Shaw figures out that his father had already been killed by Voss.
Fitz and Simmons discover that they are locked in the mechanism's room as well. As Johnson is still trying to get answers from Hinton, she is approached by Voss, who tells her that there might be a way to prevent the Earth destruction: keeping Quake from returning to the past so that she cannot trigger a massive earthquake. Thus, the True Believers attack the S.H.I.E.L.D. agents. Although the S.H.I.E.L.D. team eventually defeats their opponents, Hinton is stabbed by Voss during the fight. In her last moments, Hinton is comforted by May. She reveals that May took care of Hinton and raised her, much to May's astonishment. Before dying, Hinton informs May that Flint, the Inhuman who is known to everyone in the S.H.I.E.L.D. team except May, is the key to their success in saving everyone.
In the Lighthouse, Kasius sends Sinara to chase the fugitives on Earth and decides to punish the inhabitants by cutting down the power and releasing Vrellnexians from the sealed levels where they are contained. The survivors blame Flint for this as it would not have happened if he had turned himself over to the Kree Watch, but Alphonso Mackenzie and Rodriguez defend him. Together, they head to the level 3, where they reclaim the crate of weapons hidden by Fitz decades ago, including the Shotgun-Axe and some Splinter Bombs. Fully armed, they manage to exterminate the Vrellnexians, growing gratitude among the remaining Lighthouse's inhabitants, who ultimately decide to join them in their fight against the Kree. Meanwhile, Sinara finds the remnants of the Trawler and Kasius orders her to track down the fugitives and to bring Quake back alive.
- Clark Gregg as Phil Coulson
- Ming-Na Wen as Melinda May / Melinda May
- Chloe Bennet as Daisy Johnson/Quake
- Iain De Caestecker as Leo Fitz / Leo Fitz
- Elizabeth Henstridge as Jemma Simmons / Jemma Simmons
- Henry Simmons as Alphonso Mackenzie
- Natalia Cordova-Buckley as Yo-Yo Rodriguez / Yo-Yo Rodriguez
- Dominic Rains as Kasius
- Jeff Ward as Deke Shaw
- Joel Stoffer as Enoch
- Florence Faivre as Sinara
- Coy Stewart as Flint
- Michael McGrady as Samuel Voss
- Willow Hale as Robin Hinton
- Michele Tobin as Gretchen
- Dusty Sorg as Mouse
- Tunisha Hubbard as Ava
- Luke Massy as Hek-Sel
- McKay Stewart as Roughneck
- Jamal Akakpo as Comms Agent
- Mark Casimir Dyniewicz as Exchange Workman (uncredited)
- Phil Coulson's Prosthetic Hand
- Splinter Bomb
- Quake Gauntlets
- Grappling Claw
- Isochronus Cyclotron
- Kree Battle Axes
- Time Di'Alla (fragment)
- Owen Shaw
- Polly Hinton
- Alya Shaw
- Charles Hinton
- Calvin Zabo
- Maria (indirectly mentioned)
- Leticia (indirectly mentioned)