Welcome to Cannery Row, where everyone's pretty poor and friendships are close. The major players here are Lee Chong, who owns the grocery store; Mack and the boys, bums who live on his property; Dora, the madam of the local brothel; and Doc, the guy who owns the Western Biological Lab. You know, your basic five-man band.
Everyone on Cannery Row likes Doc. He's always got advice, a sympathetic ear, and something interesting to tell you about, so, obviously, Mack and the boys decide to throw Doc a party.
But first, they need money. So, they hatch a scheme to capture a whole bunch of frogs, which they'll sell to Doc for five cents each. Their scheme works and soon they're rolling in ... frogs. And nickels. They get everything they need for a rocking party, and set up at Doc's before he arrives back that night from a trip. Doc comes back later than expected to find his place empty, but completely trashed.
After a low period for all of Cannery Row, Mack and the boys get it together to throw Doc another party, one that he can actually attend. They do it right this time, and Cannery Row pulls out the stops to make it one stupendous party. And it is. The book ends as Doc, happy but maybe a little wistful, too, cleans up after the big shindig.