A foolish attempt at a not-too-long Gravity's Rainbow summary

It's WW2. A US army lieutenant, Tyrone Slothrop (sometimes referred to as a 'limey' by the other characters for some reason) sleeps around London. He keeps a chart of his sexual conquests on a map of London, sticking coloured stars at the locations of his fornications. Some bright spark in the government notices that about two to seven days after each of Slothrop's shags, a V-2 rocket hits in the same place. There is a spookily accurate coincidence between Slothrop's map and a map of rocket hits, both governed by the Poisson distribution. A guy called Teddy Bloat sneaks into Slothrop's work cubicle when he's not there, snapping pictures of the map.

Slothrop gets sent off, apparently on some kind of leave, to the coastal Hermann Goering casino with a couple of mates. Relaxing on the beach, he sees a beautiful woman being dragged into the sea by an octopus. He rescues her using a crab handed to him by one of his holidaymates, Teddy Bloat. Paranoia kicks in when he wonders why Bloat conveniently just 'happened' to have the crab with him: Say, where'd you get that crab?. This feeling deepens when his other friend, Tantivy Mucker-Maffick, disappears. For some reason, a man turns up who teaches Slothrop German and gives him lots of information for researching rockets. Slothrop discovers the existence of a curiously undocumented rocket, the 00000, and one of its unusual components, the S-Gerät. The S-Gerät is unusual in that it is made out of the erectile plastic Imipolex G, invented by the organic chemist Laszlo Jamf.

Slothrop flees, escaping into the Zone of post-war Europe; he is now on a Quest for the Rocket. He has a large number of adventures, being chased by some of the other characters, notably Major Duane Marvy and Ned Pointsman. He has a trip in an air balloon, where he has a pie fight with Marvy, tries to steal hash from the grounds of a great conference, and winds up on a boat called the Anubis. He falls overboard, and ambles around for a bit in different costumes (including a Russian army uniform and a pig suit). Slothrop repeatedly has close encounters with Marvy, culminating in one interesting situation where Marvy puts on Slothrop's pig suit and gets his balls cut off.

By this time, a ragtag gang of friends has sprung up to try and rescue Slothrop, who, it transpires, is apparently starting to fragment. Slothrop becomes a superhero, and then finds himself in a street, coming across a fragment of a newspaper article: though he doesn't know it, it's telling us about the Hiroshima bomb. After this, he finally splits up into entities which few are able to hold together into any kind of coherent personality. He is last sighted with certainty on the cover of an album by The Fool.

Now Slothrop is demoted from being the primary storyline, having eluded and escaped the narrative, the launching of the 00000 comes to the fore. It turns out that a psycho called Weissmann, aka Captain Dominus Blicero, has possession of the Rocket, and the S-Gerät is in fact a plastic capsule designed to contain a person. Weissmann prepares for launch. He places his sex slave Gottfried into the S-Gerät, bound and silken. The familiar smell of the Imipolex G comforts Gottfried, and he feels the exact moment of brennschluss when the rocket begins to drop. The narrative decouples at the exact moment the 00000 is about to land on a cinema. Inside the cinema, the projector has just broken down and yet on the screen are the words of a hymn by one of Slothrop's ancestors.