This issue opens in 1,000,000 BC (approx) where
Odin suggests his compatriots drink to their forthcoming heroic deaths. They are
Agamotto the 1st
Sorcerer Supreme, the 1st
Black Panther,
Ghost Rider and (female)
Iron Fist, an apeman marked with the
Starbrand and a woman possessed by the
Phoenix Force referred to as
Lady Phoenix. We met them in the
Marvel Legacy #1 (one-shot, also by
Jason Aaron) where they brought down a mad
Celestial (known as the
Fallen). Now the
1st Host of
Celestials has come for revenge. Agamotto thinks they have no chance of defending Earth against the Host. But he also wonders if they should try - he has a feeling the proto-humans around them may become a great danger in the future.

In the present
Steve Rogers (no longer in the thrall of
Hydra in
Secret Empire),
Thor (
Odinson) with his replacement for
Mjolnir (destroyed in the last adventure of
Thor (
Jane Foster)) and
Tony Stark (no longer in a coma since loads of people
Searched for him) have met in a bar (Tony's drink is non-alcoholic of course). Steve wants to restart the
Avengers. Tony thinks they should leave it to the newer heroes. But Thor says that after all they've been through recently they must regain their destiny.
Tony sarcastically asks if they should just wait for a big threat to turn up that will gather a new team around them. At which point his
Motherboard AI announces multiple massive energy fluctuations 200 miles up.
Black Panther has brought
Doctor Strange to see the contents of a deep cave below South Africa where archaeologists have been killed by radiation. There are markings on a wall including a panther head and a shape like Strange's
Eye of Agomotto.
Stephen Strange detects that this place had been sealed and protected by Agamotto's spells and he reasons that the spells failed when the
Empirikul destroyed all Earth's magic in the
2015 DrS series. And whatever large thing was kept here has now gone. Meanwhile there are very deep holes leading further down which T'Challa wants to investigate.
(This also harks back to
Legacy where we saw this cave unearthed. The wall there also had symbols for the Phoenix, Starbrand and Iron Fist, Ghost Rider's head and Thor's hammer Mjolnir which Odin wielded at the time. And the archaeologists were killed by the Fallen Celestial who summoned the Final Host. And later in the issue
Loki came and found the Celestial who obviously isn't there now.)
In
Hillrock Heights in East Los Angeles where the latest
Ghost Rider (since the
2014 All-New series)
Robbie Reyes is still trying to come to terms with the latest twist. Unlike previous GR's he wasn't possessed by the
Spirit of Vengeance but by an evil ghost. However in
Legacy he unleashed to SoV's
Penance Stare when he fought the current
Starbrand when they were both drawn to the South African cave area. Starbrand wanted to stop the freeing of the Celestial.
In Manhattan
Jennifer Walters gets rid of unwanted attention by showing her
She-Hulk face, but is desperately trying to keep her alter-ego under control. (She-Hulk is green again not grey since her Legacy issues
#159-163, but still big and angry.)
Captain Marvel (
Carol Danvers) flies out from
Alpha Flight space station to investigate the energy anomalies and finds a giant Celestial hand emerging from 1 of them. At the same time Motherboard detects the spike in energy as the Avenger trio fly around in a
quinjet. Thor wants to go up to investigate but Stark says the thing is coming down to them.
Strange and Panther find a cavern full of pods which start to open. Robbie Reyes sees large alien beetles emerge in LA and starts to fight them as Ghost Rider. And in the South African cave more of the beetles hatch out.

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