About 13 pages into the script you already get introduced to the Sandman, the alien symbiote and Green Goblin 2. The Alien symbiote comes from a meteor and it happens to touch and follow peter home without his knowledge. So it just sits in his apartment waiting....
Anyhow. we get an early fight with GG2 and Spidey that has Spidey on the recieving end of an ass kicking only to get turned around as GG2 gets pushed into a narrow alley and runs head first into a spider web clothes line hanging and almost killing Harry. Peter saves him and Harry doesn't remember much. So chalk up another mind wipe in the comic world. Flint gets turned into Sandman as he is being chased into a molecular test site and bam... becomes sandman.
MJ's career isn't doing so hot and she is a bit jealous of all the fame that Spiderman is getting. At the same time Peter is trying to find a way to propse to MJ. Gwen Stacy steps in as Peter Parker's tuter student since they both have Doctor Connors class together. She is also played up as a **** in the script and has dated Brock in the past but was nothing serious. She also introduces Spiderman during a "Spiderman Day" event and pulls an upside down kiss. This whole thing doesn't last long as Sandman is highjacking an armored truck. Spiderman kicks in and attempts to save the day. Think of this fight like the sandstorm in Mummy 2. The fight ends with Sandman getting away but not before Brock gets a snap shot of a "defeated" spiderman. When Peter finally figures out how to propse to MJ he takes her to this coffee joint and Gwen comes in only to ask Peter if he has that picture where she is kissing spiderman upside down. This does not please MJ at all.
Oh, side note... Brock, who from the script was hired only a week before (error already) and Peter are fighting for one of the staff positions on the bugle. Both are taking photos of spiderman only Brock's don't paint him in a pretty light. At the same time Aunt May and Peter are taken to the police station for some shocking news. Seems that Uncle ben's killer from the first film wasn't actually his killer. Just some guy that helped. The real killer is... You guessed it.. Sandman. So now Peter gets it personal with Sandman. He's pretty much hunting him down with no luck. Sittting by police scanners just incase. Even pushes MJ away when she tries to comfort him. He falls asleep curled up with the police scanner and this is the perfect time for the alien symbiote to make its move.. He wakes up the next morning high above the city in his black costume With the power that the alien costume gives him he easily tracks down Sandman and a massive battle goes on eventually leading to Sandman getting a load of water hit on him.
Spiderman goes back to the apartment where he meets the russian dude who bugs him for rent.. only this time Peter aint taking no ****. He tells off the guy and you see a hint of the aliens true form with the teeth and what not before he takes it off. MJ gets a new job and goes to Harry first since Peter is pushing her away. At this point Harry starts to remember everything. MJ and Harry kiss and she bolts out the door after realizing what she just did. When she gets back to her apartment there is someone waiting for her.. Green Goblin 2. He makes her make Peter meet them some place so he could force her to break up with him and go with Harry under threat of hurting Peter. Peter is suffering from the roid rage that the alien costume brings about and doesn't care. He also comfronts Brock who has been doctoring photos of spiderman. Peter proves this and gets him fired. Peter also takes the costume to doctor connors who has a lot of Lizard stuff up on the walls.. hint hint..
Next day he's going out with Gwen stacy to where MJ works as a singer where her dad is hitting her up for cash. He steals her spotlight and Gwen picks up that he's doing it to just get back at MJ and she runs out. Peter doesn't give a **** and goes off on them. MJ's dad doesn't like this and steps up to Peter. He takes him out and stops only after hitting MJ. He realizes it's the suit that is making him do these things and decides to get rid of it. Just so happens he web slings to the top of a church and attempts to get it off with no luck. Even more lucky that Brock is in the church inside. Beyond lucky is that the church bells ring and the costume melts away... and lands in Brocks hands.
Brock finds sandman and makes the team up happen to get rid of Spiderman. They kidnap Gwen Stacy and take her up a 70 story building for the classic drop scene. Both sandman and venom start kicking the living **** out of spiderman leading to MJ to beg Harry to help him. He comes to the rescue as Venom is about to impale him. Pumpkin bomb after pumpkin bomb the battle rages on. Gwen is dropped and only a matter of feet away from death she is saved without any neck injury to boot. She goes to kiss him again but Spiderman turns her down. Venom is about to impale spiderman again but Harry gets in the way taking the force.
There's a subplot about sandman doing all the crimes to raise money for his kids health but who cares about that stuff besides it's the kid who eventually tells sandman to stop kicking spiderman's ass. Venom is also shanked. So the Alien costume leaves Eddie and goes after spiderman. Peter remembers about the bell and starts hitting the bars making the noise eventually winning the battle.
MJ, Gwen and Peter are all still alive but sadly Harry isn't. At the very least Harry did forgive peter just before he died.
