Those who don’t remember the 1970s seemed doomed to repeat them. “Swingtown” (9 p.m., CBS), the latest TV series to revisit the bicentennial era, focuses on the subculture of group sex, key parties and wife-swapping. Whether “swinging” was a widespread phenomenon or merely a media fixation (remember “metrosexuals?”) seems beside the point now.

Set in a Chicago suburb on the eve of July 4, 1976, “Swingtown” follows a middle-class couple, Susan (Molly Parker) and Bruce (Jack Davenport), as they move from a blue-collar neighborhood to a tonier lakeside district, where they attract the attention of an air pilot (and dedicated swinger) Tom (Grant Show) and his wife, Trina (Lana Parrilla).

Miriam Shor plays Susan’s pal Janet from the old neighborhood, a clingy living metaphor for dowdy ways and nickel-and-dime Hamburger Helper budgeting who is horrified by Susan’s new neighbors. Watching Janet stumble upon an orgy in the rumpus room is worth the price of admission.

“Swingtown” also focuses on the town’s teens, who move rather uneasily through an era of sex, drugs and rock ‘n’ roll, particularly when all of the moms and dads are “doing their own thing.”

Few sights inspire as many giggles as Show staggering under a “Ron Burgundy” hairstyle, but “Swingtown” unfolds with a deadly solemnity. As Susan and Bruce pack up the Cadillac to move out of the old neighborhood, Bruce fires up an 8-track of “Saturday in the Park” by Chicago. His earnest daughter asks, “Dad, are you being ironic?” Bruce replies: “No, that’s your department. I just like the song.”

This brief interchange happens to be one of the more believable conversations in the pilot and a clear indication of the show’s weird tone. Recalling the 1970s without irony and discussing group sex without humor appears to be the goal of “Swingtown,” and the results are so grim they often become unintentionally hilarious.

Even a film as tragic as “The Ice Storm” had funny moments, but “Swingtown” looks back at the period through the prism of subsequent years and the onslaught of AIDS, the counterreformation of “family values” politics and a generation of divorce. Is “Swingtown” sleazy voyeurism? Or laden with judgment?

l In the 13-episode horror anthology “Fear Itself” (9 p.m., NBC), “The Sacrifice” follows the “four-dudes-lost-in-the-woods” formula of SciFi’s Saturday-night chillers. Jesse Plemons (“Friday Night Lights”) stars.

Tonight’s other highlights

¢ A court-side edition of “Jimmy Kimmel Live” (7 p.m., ABC) and “NBA Countdown” (7:30 p.m.) precede game 1 of the NBA finals (8 p.m.).

¢ On two episodes of “CSI” (CBS), agents find the charred remains of a recently released prisoner (7 p.m), Lady Heather becomes a target (8 p.m.).

¢ Randy takes charge on “My Name Is Earl” (7 p.m., NBC).

¢ The talent search continues in San Francisco and Toronto on “Last Comic Standing” (7:30 p.m., NBC).

¢ A lad seeks adventure in the new cartoon series “Marvelous Misadventures of Flapjack” (7:30 p.m., Cartoon Network).

¢ “Celebrity Addiction with Dr. Drew” (8 p.m., VH1) looks at junkies with publicists.

¢ Akon appears on the finale of “Step It Up & Dance” (9 p.m., Bravo).