Plot summary
The beacon's explosion destroys three monoliths that were being stored in the bunker, creating a dimensional rift that manifests the fears of the team. Using gravitonium, Fitz creates a device capable of sealing the rift; Coulson volunteers to deliver the device, but then collapses. The team finds out about his infection, a result of the Ghost Rider burning off the life-sustaining GH-325 drug within him. The team is forced to accelerate their plan when Yo-Yo is attacked by the manifestation of a Simmons Life Model Decoy (LMD). Coulson sends Deke to the surface to call for backup, then proceeds alone to seal the rift.
He encounters a manifestation of Mike Peterson, who claims that Coulson's experiences are just a dream and that he is dying on an operating table after the Battle of New York. Coulson overcomes his fear and is saved by the real Peterson, who responds to Deke's call and arrives with several other S.H.I.E.L.D. agents. Coulson and Peterson fight off manifestations of Vrellnexians, Lash, and Hive before managing to contain the rift. Later, the team organizes a wedding ceremony for Fitz and Simmons. General Hale, who is investigating sightings of Daisy, finds evidence that Deke is related to Fitz and Simmons.
Credits
Adapted from Wikipedia contributors, Agents of S.H.I.E.L.D. season 5. HTML formatting and reference markers removed.