Twins Edgar and Ellen live alone -- their parents disappeared years ago, and who can blame them? -- in the quaint, little town of Nod's Limbs, in a grim, gray house overlooking the cemetery and the junkyard. They spend their days avoiding Heimertz, the mysterious accordion-playing caretaker; pestering Pet, a hairy, one-eyed creature of indeterminate species and gender; and wreaking havoc on the hapless citizens of Nod's Limbs.

But wreaking havoc can incur expenses, so the twins come up with a unique fund-raising scheme: They'll nab the pets of Nod's Limbs and transform them into exotic animals they can sell for big bucks. Not a bad plan, if one of the purloined pets wasn't a lethargic python with a raging appetite....