Peter Parker is sent by the Daily Bugle to photograph Hulk rampaging through Connecticut.
As a result of a plot too complicated (and silly) to bear repeating, Spider-Man is temporarily Hulkified. It’s because of a scientist seeking revenge for stuff Hulk did, and his plan misfires. (I guess that actually wasn’t so complicated.)
It’s not a bad story, but in 1990 we’ve kind of become accustomed to stories that are a little more sophisticated than this.