A stirring profile of a strange and controversial figure, “I Am an Animal: The Story of Ingrid Newkirk and PETA” (7 p.m., HBO) says as much about the contemporary state of media and intellectual discourse as it does about animal rights or Ms. Newkirk.

A relatively obscure organization just two decades ago, the People for the Ethical Treatment of Animals has become the controversial face of the crusade against cruelty to animals. And that’s just the problem, say many PETA critics in other animal-rights organizations. Priscilla Feral, president of Friends of Animals, declares that Newkirk and PETA have “trivialized animal rights” with their media grandstanding.

“I Am an Animal” follows PETA activists as they attack a fashionable Paris boutique displaying fur coats. And, just in time for Thanksgiving, we also get to watch an undercover investigation of a turkey-processing plant. When one young activist, who had dedicated weeks and months to the project, fails to come up with usable footage, Newkirk throws him overboard in a brutally dismissive manner.

It’s no exaggeration to say that Newkirk has dedicated her life to her ideals. She had herself sterilized at 22, because she felt it was immoral to bring new infants into a world where there were so many suffering and homeless children. Her last will and testament instructs PETA to “barbecue” parts of her body when she dies to illustrate the horrors of meat eating. She also wants her skin to be turned into a wallet and other leather goods.

Newkirk insists that PETA’s “jarring” tactics are a necessity in a media world where ideas and causes are boiled down to 15-second sound bites. But her former colleague and PETA co-founder Alex Pacheco had to leave the organization. He argues that the stunts have gotten in the way of the message. This point is underscored with footage of a Hollywood PETA rally hosted by actress and pathological exhibitionist Pamela Anderson.

Newkirk’s story may be called “I Am an Animal,” but a more apt title could be “I Am a Publicity Hound.”

¢ Taped last Thursday, Comedian Ellen DeGeneres performs at the comedy festival in Las Vegas, Nev., on “Ellen’s Really Big Show” (8 p.m., TBS). Invited guests include magician Lance Burton and singers Mary J. Blige, Sheryl Crow, Barry Manilow and Wayne Newton.

¢ The 13-part series “Invention Nation” (9 p.m., Science) invites viewers to suggest ways to solve everyday environmental problems.

Tonight’s other highlights

¢ Sarah’s jealousy comes to the surface on “Chuck” (7 p.m., NBC).

¢ Chris takes a job at a Chinese restaurant on “Everybody Hates Chris” (7 p.m., CW).

¢ Claire complicates her father’s escape plan on “Heroes” (8 p.m., NBC).

¢ An overbooked wife and mother (Molly Shannon) suffers an unusual breakdown in the 2007 cable comedy “More of Me” (8 p.m., Lifetime).

¢ A plastic surgeon’s murder seems wrapped in mystery on “K-Ville” (8 p.m., Fox).

¢ Calleigh under fire on “CSI: Miami” (9 p.m., CBS).

¢ Dan follows a serial killer into the early 1990s on “Journeyman” (9 p.m., NBC).

¢ The two remaining worthies meet Brad’s mother on “The Bachelor” (9 p.m., ABC).

¢ Author Lisa Gardner appears on “Murder by the Book” (9 p.m., Court TV).

¢ “Weeds” (9 p.m., Showtime) wraps up its third season.

Cult choice

Former socialites (and cousins of Jacqueline Bouvier Kennedy Onassis) dwell on the past as they live amid squalor in the 1975 documentary “Grey Gardens” (6:15 p.m., Sundance), an inspiration for a recent Broadway musical.