Webster was once an average lab monkey confined to a cage, but his life changes when a radioactive spider bites a teen on a science field trip to the laboratory (presumably the boy heads out the door to become Spider-Man). Webster gobbles down the altered arachnid, and superpowers ensue. That night, an explosion destroys the lab. Webster escapes, while other lab animals are transformed into ominous, sharp-toothed mutants: A mild-mannered rhino becomes an otherworldly menace, a shark and a lizard merge into the Shizzlerd, and a pink octopus, a dopey platypus, and the doctor who ran the lab are fused into Doctor Octoplatypus! Webster battles the lot in a series of comic book–style capers, scaling tall buildings, slinging spiderwebs, and occasionally accepting help from other animal allies. The lightly sketched plot allows readers plenty of room to enjoy Baltazar’s gleefully goofy artwork and happy-go-lucky hero, whose antics remain steadily slapstick throughout. The author/illustrator initially created Webster as a send-up of superhero tropes; this committed creative exercise happily offers kids a gateway into the genre even as it revels in its winking homage.