Synopsis
The issue opens with an injured Ironheart and unconscious Spider-Man (Miles Morales) in a scene of forest devastation with snow and also flickering flames. Then it backtracks to explain how they got there.
Ms. Marvel (Kamala Khan), leader of the Champions, has contacted member Riri Williams about Spidey. Miles quit in Champs#4 but now he's gone missing for a couple of weeks even from his parents. He may just want to be alone to come to terms with the deal he made with the devil (see Champs#2). Under those circumstances they agree he wouldn't want his friends to go after him, but he and Riri never really bonded so Ironheart is perfect for the job. Riri remembers Miles feeling out of place in the team, and she warned him that if he quit she'd kick his butt - so now's the time to follow up on that.
She and her NATALIE AI track his cell phone usage and find he left New York City for the Upstate woods. His phone then stayed in 1 place for the last 16 days but it hasn't been used in that time.
Next day (February 2nd) Ironheart flies there from Chicago and finds a snow-laden cabin. (We are made aware that someone is watching the cabin and recording her arrival.) Riri knocks on the door and it swings open and there's a whooshing sound.
Inside she finds Miles in civvies about to make pancakes. He doesn't understand why she thinks he's been missing for 2 weeks - he says he's only been here a day. The cabin belongs to a school friend's family and he did indeed come here to sort his head out. Riri checks her watch and sees that it now reads January 18th, which is what Miles thinks is correct. She tries to leave the cabin ...
... but there's another whoosh and she finds herself entering again to meet a Miles who acts as though this is the 1st time she came in. NATALIE confirms that the time is the same as when they 1st entered. Riri convinces Miles that time is repeating itself and he's somehow been here for 16 days which has only been a day for him. Superhero Spidey is used to weird stuff so he believes her. (But Miles can't remember what film this reminds him of.)
Scientist Riri theorises they're locked in a space-time loop. But entropy still rules so each time they go through the loop should be different. Miles points out that a birthmark on her wrist has gone. (I don't see *that* as an entropy effect.) But Riri adds that they both remember a time *before* the loop, so the loop has a beginning. So someone must have started it, and they must be nearby to maintain it.
They both suit up. Ironheart hopes the place is insured because she blows a hole in the wall, taking out the door. They step outside and suddenly it's February 2nd again.
A voice shouts at them from a nearby observation tower, complaining that they've ruined his 30-day experiment. The being leaps out and names himself the Tank. He claims to be interested in Spider-Man because he's an interdimensional traveller (coming from the now-defunct Ultimate Universe). He's also interested in Small-Scale Space-Time Portals and he set 1 up here in the doorway.
Now the angry guy's mutant power kicks in and he grows giant-sized. He smashes up some trees to bury the pair. There's a green disc lying around (presumably the SSSTP) which he can apparently control. He uses it to drop bits of burning wood onto their 'grave' (debris from Ironheart's explosive exit). Which brings us to where we came in.
Riri wakes Miles up and flies them out of the woodpile. They attack the giant enemy. Ironheart fires a mini-missile at him but he creates a portal between them and another behind her so that her missile enters 1 and comes out of the other towards her. She dives out of the way and Spidey shoots webbing through 1 portal so that it comes out of the other and attaches to Tank (who has somehow come between them).
He then yanks on the webline which pulls the foe through his own portal, and the giant ends up repeatedly cycling through the portal pair. Riri predicts that he'll continue like that gradually degrading via entropy. But they alert the Forest Service so someone may be able to save him. (But a bit later the portals implode and Tank's gone.)
Miles asks Riri why she came here. He thought she didn't like him. She says they're team-mates and friends, and team-mates have each other's backs. Miles hopes his friends can give him some time to sort himself out. Riri says it's a deal as long as he keeps in touch so they don't think he's dead (or trapped in a time-loop). And by the way the film was Groundhog Day.