“Friday Night Lights” (7 p.m., NBC) wraps up its fourth and second-to-last season with a Thanksgiving episode. The show, set in Dillon, Texas, a football-crazy town, ends its season just as many football fans are beginning to dream of a new season.

The odd timing of these events owes to the show’s peculiar hybrid status. First-run episodes of “Lights” air first on DirecTV before airing later on network television. The satellite service DirecTV has recently arrived to rescue another little-watched but highly acclaimed series. But if viewers want to catch the next season of “Damages,” starring Glenn Close, they should know that it will be available only on DirecTV.

“Lights” concludes on a somber note. But why should this episode be any different? “Friday” deserves all the praise it has received. And its two main stars, Kyle Chandler and Connie Britton, are up for Emmys. But “Lights” follows the dubious philosophy that in order to be taken seriously, you have to banish any trace of humor or levity.

If you were to watch “Lights” tonight for the very first time (and I highly recommend that you do), you would see a principal facing a possible firing, a miserable reunion between two former high school sweethearts, two young men facing possible jail time and a football game between rival high schools elevated to the level of World War III.

Two Thanksgiving dinners become center stage for stilted language and heartfelt speeches. The lightest moments involve a familiar face and less-than-stellar football star. And even he gets his heart stomped on for what seems to be the 30th time. Life is relentlessly grim in Dillon, Texas, and that’s one reason this terrifically shot, wonderfully acted show remains more admired than loved and more critically acclaimed than watched.

• Documentary-style television loves parenting in the extreme.

TLC has cornered a market on shows about multiple births and huge families. We’ve seen whole series on MTV devoted to teenage mothers, and BBC America devoted at least one hour to women who care for very expensive and frighteningly lifelike dolls. Add “My Child is a Monkey” (8 p.m., National Geographic) to the hopper.

We meet folks who adopt primates as surrogate babies and put them in diapers and strollers, and call them “monkids.” I monkid you not!

Tonight’s other highlights

• Scheduled on “48 Hours Mystery” (7 p.m., CBS): a federal prosecutor, kidnapped on his birthday, recalls his ordeal.

• A scandal-plagued Texas Congressman (Tom Hanks) becomes a passionate advocate for the Afghan resistance in the fact-based 2007 drama “Charlie Wilson’s War” (7 p.m., AMC), directed by Mike Nichols.

• On back-to-back episodes of “Bones” (Fox), back-to-school (7 p.m.), the gravedigger did it (8 p.m.).

• Joe worries about Allison’s attachment to a case on “Medium” (8 p.m., CBS).

• A confrontation leads to collision at sea on “Whale Wars” (8 p.m., Animal Planet).

• Ethical dilemmas on “Primetime: What Would You Do?” (8 p.m., ABC).

• Help arrives in the form of Claudia Donovan from “Warehouse 13” on “Eureka” (8 p.m., Syfy).

• A double kidnapping defies reason on “Flashpoint” (9 p.m., CBS).

• William learns of a rival for his title on “Pillars of the Earth” (9 p.m., Starz).