Synopsis
Wasp (Nadia Pym) is carrying baby Kang and flying through the timestream courtesy of a friendly Kang's time machine (that he wore as a shoulder-piece). As she passes windows into various times she is attacked by giant grabby hands which she has to fight off. All the while telling the infant (and us) what she's doing here:-
Vision abducted the baby to stop him from becoming Kang, but instead it caused time problems and multiple Kangs to attack the Avengers. The multi-Kangs retaliated by killing all the Avengers (on this team) as babies except Hercules. But a combination of the friendly Kang and a magic necklace Herc got hold of have stopped the Avengers from fading into non-existence. Now Wasp has been sent to return baby Kang to his rightful place to set everything back to what it was.
Back on Earth the Avengers are still fighting the Kangs. 1 of them freezes Thor's hammer in time. Another phases out of time to avoid Vision and then tries to age him to death. But unexpectedly the synthezoid isn't affected. Then Vizh ghosts his arm into the temporal trap and retrieves Mjolnir before Thor is reverted to her human form.
At this point the main Kangs (Kang-Prime and Scarlet Centurion) notice Wasp has taken the baby into the timestream and follow her. When they catch up with her it distracts her so that 1 of the hands can pull her into a reality ...
... and she finds herself 500 years in the future with the descendants of the Priests of Pama. Vision had left the baby in the Priests' care in the present, and it turns out the the surrounding paradox had granted them temporal powers which had grown stronger with the generations. They now feed upon time itself, upon seconds which no-one will miss.
Their mission is to protect time from paradoxes such as those that Kang creates. But ironically their powersource, the Eternal Flame of Pama, is fueled by those very paradoxes.
Back in the present the other Kangs are still fighting the Avengers. 1 of them searches time for reinforcements but stumbles across the grave of Avenger X breaking open (as we saw in a postscript to #1). The Kang is shocked that he knew nothing of this. But our team continues to be on the losing end of the fight, and Spider-Man wishes Steve Rogers was here to give them an inspirational speech. Cap-Sam Wilson just doesn't cut it in that respect.
The Priests show Wasp what is happening. And also that the the pursuing 2 Kangs are battering their way into this time. They tell Nadia she can save her teammates by letting them give baby Kang to the Flame. The paradox that is Kang will then be no more.
But Nadia can't bring herself to do it. She flies the baby to a place of safety and then dives herself into the Eternal Flame ...
... the next thing we see is Wasp leading the other Avengers through the same Flame. As she explains to the Priests the Flame has removed the paradox of their continued existence by undoing their child-deaths.
Then she sends Spidey to get the baby and proceeds to part 2 of her plan. Thor's hammer smashes the barrier that is keeping the Kang and Centurion out. But when they break in the combined Priests propel them into the Flame which appears to consume them.
Then Wasp takes the baby and all the Avengers into the timestream where they restore baby Kang to his crib. And then back home.
Wasp is worried that she's just restored 1 of their greatest foes. But Vision whispers to her a reason why Kang had to exist. (So why did he try to wipe him out then?) But Captain America has a plan to end the threat permanently.
To be continued ...