Parallel dimensions converge on “Lost” (8 p.m., ABC). Why else would Desmond have attacked Locke, if he hadn’t “remembered” that nasty incident by the well?

Meanwhile Locke, or whatever he is now, gets his wish as his posse joins forces with Jack and crew. With so many dead or departed characters showing up and chatting with Hugo, I just want to know if we’ll ever see Juliet again. Was she lost forever when she “reset” time with the hydrogen bomb? Or will we simply have to wait until ABC cancels “V”?

• Coach Schuster challenges the team to channel their inner Madonna on tonight’s “Glee” (8 p.m., Fox). Cue the campy musical numbers and blather about female empowerment.

Funny, whenever I think about Madonna, I’m reminded of the line from “This Is Spinal Tap,” when an unnamed critic dismisses their album as “Treading water in a sea of retarded sexuality and bad poetry.” Considering her role in putting marketing ahead of music and in paving the way for vulgarians like Britney Spears, the idea of celebrating Madonna seems horrifying — to me, at least.

Meanwhile, “American Idol” (7 p.m., Fox) turns to songs of inspiration on the eve of the “Idol Gives Back” special. Let’s hope at least a few of these numbers include songs of a more recent variety. Two weeks of Beatles and Elvis covers have asked the kids to reach back half a century for inspiration. And the group medleys of golden oldies have had an “Up With People” quality that have made the lame Ford commercials seem comparatively edgy.

For further proof that all music and musical acts can be recycled, see New Kids on the Block on “Late Night with Jimmy Fallon” (11:35 a.m., NBC). Rosario Dawson and Tony Siragusa also appear.

• Jamie Lee Curtis narrates “Dirt: The Movie” on “Independent Lens” (9 p.m., PBS, check local listings). “Dirt” does a good job of mixing science, interviews and animation as it profiles the living “skin” of our planet, a resilient organic compound that makes life possible and asks for little in return. “Dirt” makes the case that societies that live in concert with the soil tend to thrive, but those that abuse it face catastrophe.

• “The Lazy Environmentalist” (7 p.m., Sundance) enters a second season of championing the search for common-sense green solutions to everyday living.

• “Burma VJ: Reporting from a Closed Country” (8:30 p.m., HBO) profiles underground journalists who risk imprisonment and execution to document life under a military dictatorship.

Tonight’s other highlights

• “Nova” (7 p.m., PBS, check local listings) looks at California’s efforts to cut greenhouse gases.

• The “30 for 30” presentation “Silly Little Game” (7 p.m., ESPN) looks at the growth of fantasy sports leagues.

• “Frontline” (8 p.m., PBS, check local listings) examines the systematic sexual abuse of poor boys in Afghanistan.

• Chad accompanies Anna to a global summit on “V” (9 p.m., ABC).

• The family frets when Amber’s ex returns on “Parenthood” (9 p.m., NBC).

• Ballet can be murder on “Law & Order: Criminal Intent” (9 p.m., USA).

• A reported suicide on a posh horse farm is more than it first appears on “Justified” (9 p.m., FX).

• “Deadliest Warrior” (9 p.m., Spike) returns for a second season of comparative toughness.