What’s On This Week

8 P.M. (Disney) LEMONADE MOUTH (2011) Believe in yourself. Follow your dreams. Celebrate family. And, oh yeah, rock on. Those are just a few of the precepts explored in this Disney Channel original movie about five very ordinary, music-obsessed high school students who meet in detention, do the obvious and form a band — and become the voice of their generation. The cast, above from left, includes Blake Michael (who landed the role through an open casting call), Adam Hicks (“Zeke and Luther”), Hayley Kiyoko (“Wizards of Waverly Place”), Bridgit Mendler (“Good Luck Charlie”), Naomi Scott ( “Life Bites”) and Nick Roux (“What Would Jane Do”).

3 P.M. (Fox) THE DR. OZ. SHOW John Quiñones of “Primetime: What Would You Do?” on ABC (Fridays at 9 p.m.) reveals how ordinary Americans respond to uncomfortable situations — in this case, the staged scene of a mother arguing with her daughter about her weight and urging her to undergo a gastric bypass procedure. Two unwitting bystanders explain why they intervened.

8 P.M. (NBC) FRIDAY NIGHT LIGHTS For viewers who were unable to catch this critical favorite’s final season on DirecTV last fall, the action is repeated in this network presentation of Season 5, which kicks off as Coach Taylor (Kyle Chandler, above right) tempers high expectations for East Dillon’s coming season. Meanwhile, his wife, Tami (Connie Britton), is increasingly frustrated by her new job as a guidance counselor at the school. Vince (Michael B. Jordan) and Luke (Matt Lauria) work to recruit a new player for the Lions’ squad. And two alumni prepare for college.

8:30 P.M. (13) NEED TO KNOW The state of the Gulf Coast and America’s energy policy, one year after the BP oil spill.

9 P.M. (CMT) CMT’S NEXT SUPERSTAR The nine remaining singer-songwriters are divided into trios for their second challenge — to sing for money on Lower Broadway in Nashville — in this competition series from the father-and-son producers Nigel and Simon Lythgoe (“American Idol”). The group with the fewest tips must “sing to survive” that night at a honky-tonk before the guest judge, Trace Adkins, after which one contestant will be sent packing.

9 P.M. (National Geographic) HOOKED: CHASING MARLIN Marine experts embark on a deep-sea expedition to study the migratory patterns of the striped marlin. The mission: to tag this game fish, which can reach speeds of nearly 50 miles an hour. But pity the angler who is pulled overboard by a 10-foot-long blue shark.

9 P.M. (Animal Planet) KILLER OUTBREAKS Your next trip to the office could be fatal, and not for reasons that you might imagine. Some of the world’s most devastating diseases can be found on harmless-looking desks and doorknobs. In this series premiere, the Centers for Disease Control, the New York Police Department and the Federal Bureau of Investigation respond to the threat of anthrax.

10 P.M. (Science) BUILD IT BIGGER Danny Forster travels to Melbourne, Australia, where a drought has afflicted the region since 1997, leaving reservoirs at record lows and prompting serious water restrictions. The state of Victoria is building the largest desalination plant in the Southern Hemisphere, with plans to convert up to 396 million gallons of seawater into fresh water annually — allowing residents to resume watering their lawns and soaking in their bathtubs. But with tourism a top industry, the government has had to find creative ways to mask the noisy industrial process. Voilà! A plant disguised by manmade sand dunes that help deaden the sound and conceal the building, and pipes that are buried beneath the seabed for nearly three-quarters of a mile beyond the beach. In addition, the structure is topped with the world’s largest green roof: more than 275,000 square feet of indigenous plants.

10 P.M. (Starz) CAMELOT Merlin (Joseph Fiennes) seeks a sword worthy of a king. Arthur (Jamie Campbell Bower) is dramatically changed by a conversation with Guinevere (Tamsin Egerton).

10 P.M. (Syfy) SANCTUARY Season 3 returns from hiatus with 10 new episodes, picking up as Dr. Helen Magnus (Amanda Tapping) and the team are sentenced to death. Polly Walker reprises her role as Ranna, the city leader who holds the fate of the group in her hands.

10:30 P.M. (IFC) THE WHITEST KIDS U’KNOW This comedy troupe begins its fifth and final season with sketches that include “Baked Beans,” “War Letter” and “Finger Ring Friends.” KATHRYN SHATTUCK