Synopsis
A mega-powerful being called the Lost One is hunting down all the Beyonders for revenge and they've gone into hiding. The 1 we call *the* Beyonder came to the Avengers for help. 1st he secretly guided them to collect weapons against the foe (in the All-Out-Avengers mini-series). In #1 of the current mini-series they found him out and he explained the situation. And they captured a minion Tiamok Rath who the Lost One sent against them. Last issue Beyonder reverted to operating behind the scenes and led the team to find an alien who can boost superpowers.
Now we see that the Lost One is hovering outside Earth's atmosphere, kept at bay by an improved planetary defence shield the Beyonder had helped create. Tiamok sits in her Avengers prison cell waiting. (Last issue she was able to detect Beyonder's background monologue but he's now taken steps so she can't hear it. Which raises the question who in their reality is he speaking to, if not us readers?) And more minions, the Black Order, have infiltrated Avengers HQ. Beyonder reminds us that these ex-warlords of Thanos have since served other masters, but he says that now they have a plan to strike out on their own.
Captain America and Captain Marvel are in the HQ guarding the 4 crystals that now power the defence screen. Carol Danvers reports that Black Panther, Iron Man, She-Hulk and Thor entered the teleport system to join them but haven't arrived. She suspects that somehow the Order have trapped them in the system. Steve Rogers sends her to delay the invaders while he calls for a genius to solve the problem.
Tony Stark and T'Challa are obviously unavailable so he phones Lunella Lafayette (Moon Girl) riding on Devil Dinosaur who asks him to put the phone next to the controls and she'll take it from there. Meanwhile CapA has to deal with the Black Order's leader Corvus Glaive who's blasted his way into the room with his namesake weapon. While the battle carries on Lunella reports that she's located the missing Avengers and they'll be free in half a minute. But she's also detected how the Order got control of the system and she cancels that. Cap asks her to port the 4 Avengers to this room which she does and phones off.
Meanwhile CapM has defeated Black Dwarf and Ebony Maw but Black Swan is giving her some trouble. CapA sends She-Hulk to her aid in time to stop a killing blow. CapM then strikes down Proxima Midnight while Thor beats up Corvus Glaive. Black Dwarf is back to tackle She-Hulk while Black Swan distracts Thor from CG who diverts to help hitting Shulk.
Then Black Panther and Iron Man discover that the shield is going down even though the crystals are at full power. CapA calls out to Beyonder for help as the shield finally fails and the Lost One arrives to free Tiamat and they both go to the battle area. Apparently the Black Order were supposed get the shield down but Corvus Glaive grovellingly apologises for failing. But it turns out the Lost One didn't do it either (Tiamat does all his speaking for him). Beyonder's voiceover suggests *he* is responsible.
However now he's here the Lost One's taking the crystals. The Avengers oppose him but he fairly easily disposes of them (CapM and Thor take 2 shots). Then he reaches for the 4 crystals but they vanish. Iron Man detects their energy signatures in 4 structures that have just appeared in orbit. They discover that the shield is on again but much stronger, and they're not in control of it. And they realise that the Beyonder's plan was to trap the Lost One on Earth with them.