Boogie, oogie, oogie

Nigel Lythgoe, Mary Murphy and Vanessa Hudgens all return for season 15 of “So You Think You Can Dance.” Ratings for the reality-competition series have dropped drastically — it averaged 2 million viewers last year compared with 10 million-plus in 2006 — so don’t be surprised if this is the show’s last dance.

7 p.m., KMSP, Ch. 9

Weight of the world

A fashion magazine advice columnist gets some guidance of her own in “Dietland,” a new comedy that takes an unflinching look at body shaming and sexism in modern-day America. Joy Nash is winning as the sympathetic heroine, especially when she squares off against her boss, played with an impenetrable layer of frost by Emmy winner Julianna Margulies.

8 p.m., AMC

The torchbearer

Bobby Kennedy is being remembered with a slew of specials, two of them premiering on the eve of the 50th anniversary of his assassination. Both “1968 Robert F. Kennedy” (8 p.m., Decades) and “RFK: The Kennedy Family Remembers” (9 p.m., History Channel) feature interviews with the late politician’s children.

Neal Justin