This “Star Wars” hype is getting out of hand. A few weeks back I was at a supermarket checkout when my cashier stopped what she was doing to have her picture taken with guys dressed as Imperial Storm Troopers and Darth Vader. I have expected to see Jar Jar Binks in the pet food aisle.

The “Star Wars” promotion will even invade the Animal Planet. The critter channel offers “Animal Icons: Star Wars Creatures” (8 p.m., Animal Planet). George Lucas discusses how he came up with the ideas for the menagerie of furry and scaly creatures that populate the six “Star Wars” features. We hear from illustrators and producers who explain the “evolution” of the idea for Chewbacca. Apparently Lucas thought of Chewy as something like the loyal family dog — but a dog who could also fly a space craft at warp speed.

Technicians and actors including Mark Hamill, Harrison Ford and Carrie Fisher discuss how Lucas would send production teams to zoos to study the movements and behavior of real animals as they were concocting the costumes and digital effects for nonhuman characters including the polar bear-like Wampa, the camel-ish Tauntaun, the swamp-dwellers of Dagobah, forest Ewoks and winged Waddos.

Season finales

• Red gets a whiff of the gang’s basement shenanigans just as Eric prepares to leave for Africa on the hour-long season finale of “That ’70s Show” (7 p.m., Fox).
• Tyra Banks and her coven of beauty wizards pick a new winner of “America’s Next Top Model” (7 p.m., UPN).
• Graduation looms on a 90-minute episode of “Smallville” (7 p.m., WB). The movie tie-ins continue here, with an eight-minute trailer for the forthcoming big screen “Batman” feature.
• The custody battle gets ugly on “Kevin Hill” (8 p.m., UPN).
• A fatal train derailment results from a despondent man’s suicide bid on of “Law & Order” (9 p.m., NBC)

Tonight’s other highlight

• Three will become two as the votes are tallied on “American Idol” (8 p.m., Fox).