Impossibly good-looking characters harbor a dark secret about a missing friend — or frenemy, as the case may be — in the new teen melodrama “Pretty Little Liars” (7 p.m., Family). Over the course of the pilot of this “Desperate Coeds,” we discover that one ravishing beauty has been romantically entangled with a guy who turns out to be her teacher. Another moody beauty engages in a public display of affection with another female character. Notes are passed, and threats implied. People spend a lot of time in towels in a gym locker room.

But it’s hard to pay much attention when distracted by the maudlin piano score, the pregnant pauses and, did I mention, impossibly pretty cast. “Pretty Little Liars” airs on the Family Channel, but I could swear I was watching a preview from SOAPnet. For all of the young flesh on display, this seems like a real throwback to an old-fashioned afternoon sudser.

l Spike TV gets into the headlines-on-the-high-seas game with the one-hour special “U.S. Navy: Pirate Hunters” (10 p.m., Spike), a documentary look at a Navy ship participating in an international effort to fight piracy in the maritime trade lanes off Somalia.

While this is clearly about a military operation, it all too often unfolds like an episode of “Cops.” At one point, the squad catches a boat of pirates red-handed, only to be ordered to let them go because they dumped their weapons in the sea prior to apprehension. Frustration mounts when they close in on a hostile vessel only to watch as the pirates board another, larger ship containing a shrouded cargo that turns out to be hundreds of starving refugees. Once the seagoing terrorists blend in with these huddled masses, it’s difficult for the sailors to tell guilty from innocent. And no amount of technology or firepower can help them.

l “Explorer: Talibanistan” (9 p.m., National Geographic) visits the border region between Afghanistan and Pakistan where tribal allegiances transcend national identification and make efforts to control or marginalize this al-Qaida haven very difficult.

Tonight’s other highlights

• Fifteen eager chefs endure the blast furnace of Gordon Ramsay’s personality on “Hell’s Kitchen” (7 p.m., Fox).

• The regionals competition arrives on the season finale of “Glee” (8 p.m., Fox). Olivia Newton-John, Josh Groban, Idina Menzel and Jonathan Groff cameo.

• A health emergency brings out the Coast Guard on “Deadliest Catch” (8 p.m., Discovery).

• Alicia’s client points fingers at a group of prominent men on “The Good Wife” (9 p.m., CBS).