At the start of this issue, some doctors are about to perform surgery on a young man. As they prepare him, it's revealed that he was went flying through a truck windshield, and has millions of tiny pieces of glass scattered through his internal organs, and that every one of them will have to be removed. Peter Parker watches this, before being approached by a doctor who asks who he is. Peter explains that the man being operated on saved both his and Mary Jane's life, by pushing them out of the way of a speeding truck. The doctor then says that in addition to his injuries, the man absorbed a deadly chemical toxin, which could kill him. Fortunately, there's an antidote, which is being taken over by ambulance. Upon hearing this, Peter runs off.
Since there's a chance that the antidote could be delivered too late to save the man, Peter decides to change to Spider-Man and follow the truck, to make sure that nothing goes wrong. He also thinks that he's heard of the toxin infecting the man before, and that like snake venom, it attacks the nervous system. Spider-Man's mind then flashes back to when he and Mary Jane were on a date, and then a truck started speeding towards them due to the driver losing consciousness. Not knowing whether he should reveal his spider powers whilst saving his life, Peter hesitated before being pushed out of the way by the man who's now in surgery. However, as a result the man went flying through the windscreen, and also absorbed some of the toxin that the truck was carrying, leading to his present condition.
Spider-Man reaches the ambulance that is carrying the antidote, but is surprised to find the guards at it all unconscious, and the antidote taken. Spider-Man notices that the ambulance has been taken apart, as if by many hands, and guesses that Doctor Octopus attacked it. Following the trail, he finds that the culprit is none other than Medusa of the Inhumans. Spider-Man at first thinks that he's made a mistake, before seeing the antidote in Medusa's belt. Spider-Man asks for it back, but Medusa insists that her need for it is desperate, and so attacks Spider-Man. Spider-Man attempts to tell her why he needs it, but Medusa ignores him and knocks him out, not noticing that Spider-Man managed to get a spider-tracer on her before losing consciousness.
Spider-Man wakes up, and is shocked to see that he only has an hour to get the antidote before the boy dies. He then follows the signal from his spider-tracer, wondering why Medusa is so much more ruthless than in the past. Spider-Man manages to find Medusa at Coney island, where she immediately starts attacking Spider-Man once more. Medusa manages to get rid of Spider-Man by throwing him onto a roller coaster which has some broken parts of the track up ahead. Spider-Man successfully stops the roller coaster and save the innocent people on it, but in the confusion Medusa has gotten away again.
Medusa then heads to a hideout of the Inhumans', where Karnak asks her if she has the cure for Falzon, a member of the Kree. Medusa does, but before she can explain why she was delayed, Spider-Man bursts in and starts attacking the Inhumans, saying that nothing will stop him from getting the serum. However, when he gets to Black Bolt, the king of the Inhumans simply stands there, and Spider-Man can't bring himself to attack him. Spider-Man then explains to Black Bolt why he needs the serum, and Karnak gives it to Black Bolt after giving some of it to Falzon. Black Bolt then flies to the hospital, and gives the antidote to the man, which is a success.
Afterwards, the Inhumans explain that they needed the serum for Falzon because he needed to deactivate a Kree weapon which could have destroyed the entire population of Earth, and had been weakened by one of it's booby-traps, explaining why there was such dire need for him to receive the serum.