Dan Mathews is director of international campaigns for the animal-rights group PETA -- People for the Ethical Treatment of Animals -- one of the most annoying and powerful pressure groups in the world. That's a bland title for someone who gets paid to splash fake blood on furs, parade publicly in underpants, and impersonate priests, butchers, and root vegetables.

In his memoir, Committed, Mathews seems virtually pre-selected to rouse the rabble on behalf of the voiceless. Born to a poor and unstable single mother with progressive political views in conservative Orange County, California, he grew up overweight and gay, hobbled by his oozing ingrown toenails and a predilection for musical theater. Taunted and pummeled by his schoolmates, young Mathews empathized with the flounder on the end of a fishhook, the cat tortured by bullies. If you lay it out this way, one might ask, why wouldn't Mathews become an animal-rights campaigner?

Committed is fast out of the gate: Mathews loses the weight, morphs into a hunk, and lets his freak flag fly. He spends his early twenties in Italy working as a model/gigolo, then returns to the United States to take an entry-level job at PETA. He arrived at his convictions early, and they never changed. But PETA did. At the time Mathews joined the group, in the mid-1980s, PETA was associated with elderly cat lovers and antivivisection posters. It spread its message with grim ads that the TV networks eventually refused to air: They made viewers switch channels. PETA was competing with other pressure groups for an ever more limited attention span. Mathews's genius was to lure young people to the cause by enlisting the support of vegetarian celebrities like Morrissey of the Smiths and Pamela Anderson. They were seen as hip, and soon PETA was too.

If this sounds like caving to the lowest common denominator, at least Mathews admits it. "For many years I pushed campaigns which appealed to people's intellect and compassion," he writes. "But as cable TV and the Internet helped mold an escapist society hungrier for entertainment than education, serious topics began taking a backseat to scandal and sensation, and we at PETA had to dream up flashier ways to vie for people's attention." Enter the lettuce bikini and supermodels wearing even less.

Does PETA's focus on the fabulous trivialize the group's message? Possibly, says Mathews, but there's a greater good. "A little strategic exhibitionism can enable a small handful of activists with no budget to reach millions," he writes. It's difficult to argue with the group's success: PETA has more than 1.6 million dues-paying members, and its campaigns are responsible for, according to Mathews, stopping General Motors' crash tests using pigs and other animals, ending Gillette's product testing on rabbits, closing all American stores owned by the giant South Korean fur company Jindo, and banning the production and sale of foie gras in California, among other feats.

Committed gives short shrift to the history of the animal-rights movement and civil disobedience, and it doesn't offer nuanced arguments for animal protection. We also don't hear a peep about PETA's more controversial practices, like euthanizing animals taken from substandard shelters or distributing violent cartoons at elementary schools. Mathews gives us some revolting descriptions of animal cruelty to justify PETA's actions, but he keeps the preaching to a minimum. The result is a breezy and curiously sunny memoir, filled with gossip, campy humor, and some delightfully bitchy asides. On looking through old yearbooks, a passion of his: "It's fun to guess who was the slut, who was gay, and who became governor. Sometimes it's all the same person."

At times, one suspects there's a sad clown lurking in Mathews's closet (he spends Saturday nights watching Lawrence Welk reruns, for example), but for the most part Committed reveals the larky spirit of someone delighted with the social and political niche he's carved for himself.