1) “Planet Earth III” opener, 8-9:09 p.m., BBC America. At 31, David Attenborough led a TV voyage to Raine Island (shown here), a 79-acre speck near Australia that is vital to green turtles. Now, 66 years later, the opener of this eight-week series (which he narrates) includes a returns to Raine. That’s in an episode filled with great footage and smart narration. Previous “Planet Earth” episodes rerun all day.
2) “Saturday Night Live,” 11:29 p.m., NBC. Here’s a rerun of the season-opener. It started beautifully, with Pete Davidson talking quietly about comedy and tragedy, then switching into a sharp monolog. Then it sagged; despite brief moments with Taylor Swift and Travis Kelce, it was mostly flat and bland. Fortunately, the net twoepisodes were much better. We’re hopeful for the rest of the season.
3) “Cowboys and Aliens” (2011), 8 p.m., CW. This mini-network seems to be in a state of perpetual flux. It had planned to put “Masters of Illusion,” its magicians show, here. Now that moves to Mondays … sending “FBoy Island” to Fridays. (“FBoy” used to be on Thursdays, but then switched nights with comedies.) For tonight, we get Harrison Ford, Daniel Craig and some aliens.
4) Football, 7:45 p.m. ET, CBS. This may be the night’s best match-up, with Louisiana State (ranked No. 14) at Alabama (No. 8). The 7:30 games include Washington (No. 5) at Southern California (No. 20) on ABC and Purdue at Michigan (No. 3) on NBC. The 3:30 p.m. ET games include Missouri (No. 12) at Georgia (No. 2) and Oklahoma (No. 9) at Oklahoma State (No. 22).
5) “A Dash of Christmas,” 8 p.m. ET, Great American Family. Laura Osnes is a do-it-all talent who has two Tony nominations (best actress in a musical) and has done five Hallmark movies. She switches to GAF for this story about an encounter with a small-town baker. There are no surprises, so “Dash” survives on pretty pictures and Osnes’ charm. Hallmark counters at 8 with “Never Been Chris’d.”