If the standup special “Robert Klein: Unfair and Unbalanced” (9 p.m., HBO, today) seems a tad old-fashioned, Robert Klein is the last guy to disagree. He reminds us that he hosted the very first HBO special back in 1975. And he admits that he was the first comic to use the “F-word” on the premium network. He’s not entirely proud of that, observing that obscenity has become a comedy crutch and a substitute for wit.

Klein opens his act with a full orchestra, performing a fake-gospel number about his hopes for the president and his advice for Obama not to fall into the thicket of sexual scandal that ensnared Bill Clinton. It’s both impressive and a tad dated, as if Klein were still milking headlines from 2008, or 1998. In fact, much of Klein’s political material seems well beyond its expiration date. A roundup of “family values” champions who have been implicated in sex scandals seems incomplete, because several more have emerged since he wrote, or performed, this material. At one point he goes way back to his work on behalf of the Mondale and Dukakis campaigns. Viewers who miss Dukakis jokes should not miss this.

Klein is most amusing when he abandons current (or historical) topicality to concentrate on himself and the indignities of growing old. When he unleashes his sharply tuned gift for observation, you can see how he might have influenced a young Jerry Seinfeld. If Seinfeld could afford HBO way back in 1975.

• In the preposterous shocker “Stonehenge Apocalypse” (8 p.m., Syfy, today), the ancient stones come to life, destroy the Earth’s power grid and create havoc on behalf of their alien creators, who have been waiting very, very patiently for just the right moment. Look for Hill Harper (“CSI: NY”) and Misha Collins (“Supernatural”) to polish their acting resumes in this gem.

• What if the Karate Kid attended Hogwarts and spent a Night at the Museum? You’d then get a sense of the derivative grab-bag nature of the hourlong live-action mystery adventure “Unnatural History” (7 p.m., Sunday, Cartoon Network). And maybe a sense of its gee-shucks fun, too.

As “Unnatural” begins, we see an elderly scientist poisoned by a blow-dart and chased by ghosts. Cut to a Buddhist temple, where the impetuous teen Henry Griffin (Kevin G. Schmidt) studies martial arts. The son of anthropologists, he’s been everywhere and witnessed fantastic phenomena. In fact, he’s so worldly and smart that nobody much believes him. This becomes a distinct disadvantage when his parents think he’s had one adventure too many and pack him off to Washington to live with his buttoned-down uncle Bryan (Martin Donovan) and his craven, consumerist and competitive cousin Jasper (Jordan Gavaris).

Once in Washington, he enrolls at an elite museum academy and discovers that his beloved mentor has died. He’s the mystery man from the first scene. And Henry is quickly convinced (in a scene too good to give away here) that his death was anything but natural. He quickly sets out to solve the murder, a task that puts his high school social standing, and very life, in jeopardy.

Blending the right amount of sophistication and whimsy, “Unnatural” is the antidote to the prevailing and poisonous depiction of teens and ‘tweens as selfish, cruel and incurious dolts. You don’t have to be 12 years old to appreciate “Unnatural History,” but it will make you wish you still were.

• Everything television touches turns to television. The carpenters, home-buyers and real estate agents who populate shows about home design, renovation and sales slowly become “performers,” and, if they are lucky, “stars.” So why am I surprised, if not a little disappointed, that HGTV has tinkered with the machinery of “Design Star” (9 p.m., Sunday, HGTV)? Returning to New York and now produced by Mark Burnett, the series enters its fifth season with a special accent on performing for the camera. Not only will the 12 designers have to outdo each other in making spaces beautiful and functional, they will be judged on how well they might be able to host their own show. In short, “Star” now trumps “Design.”

• Sookie continues her search for Bill as “True Blood” (8 p.m., Sunday, HBO) enters its third season. Just don’t call her Snookie.

Today’s highlights

• Bulldog owners think twice about breeding on “It’s Me or the Dog” (7 p.m., Animal Planet).

• On tonight’s “Doctor Who” (8 p.m., BBC America), a drilling project puts the entire planet in peril. You don’t say.

• Scheduled on “48 Hours Mystery” (9 p.m., CBS): Good and evil meet in a posh locale.

Sunday’s highlights

• Scheduled on “60 Minutes” (6 p.m., CBS): cyber war scenarios; Robert Ballard’s underwater adventures.

• Sean Hayes (“Will & Grace”) hosts the 64th Annual Tony Awards (7 p.m., CBS).

• “Extreme Poodles” (8 p.m., TLC) looks at eccentric groomers and owners.

• “Behind the Music” (8 p.m., VH1) profiles Christina Aguilera. The singer then performs on “Storytellers” (9 p.m.).

• “Breaking Bad” (9 p.m., AMC) concludes season three with Jesse on the lam and Mike in hot pursuit.

• Davis plots something to cure post-Mardi Gras depression on “Treme” (9 p.m., HBO).