#Worth Watching: Titanic Mystery and ‘Primates’ on PBS, Sundance’s A+ ‘A Word,’ Protest Protocol on ‘black-ish’

Secrets of the Dead: Abandoning the Titanic (10/9c, PBS, check local listings at pbs.org): Notwithstanding the James Cameron blockbuster, the tragedy of the Titanic has always held outsized fascination in the culture. PBS’s engrossing historical series looks into one of the more mystifying aspects of the sinking: As the evacuation was underway, a nearby ship’s lights were spotted, but to everyone’s horror, it sailed away from them, leaving more than 1,500 passengers to a watery fate. What was this mystery ship? Secrets follows investigators who examine eyewitness accounts and records of vessel locations to get to the truth. (The 1912 inquiry that blamed Capt. Stanley Lord and the Californian proved to be incorrect.)

Nature: Primates (8/7c, PBS, check local listings at pbs.org): A three-part Nature miniseries, filmed over two years during 28 expeditions, explores the many species of our closest animal kingdom kin. In the opener, “Secrets of Survival,” cameras observe life-preserving strategies among the baboons (facing leopards), lemurs, rhesus macaques, bearded capuchins and a silverback gorilla showing his gentler nature as he tends to offspring in the Congo basin.

The A Word (11/10c, Sundance TV): The warmly affecting family drama from the U.K. returns for a third season. The story jumps two years later in the lives of the Hughes family, in the wake of the messy divorce of Alison (Morven Christie) and Paul (Lee Ingleby) and the separation’s impact on 10-year-old autistic son Joe (Max Vento). The boy is so rattled he even rejects his signature headphones, which means it may not be the best time for older sister Rebecca (Molly Wright) to return from university with some eye-opening news.

black-ish (9:30/8:30c, ABC): The ever-topical family sitcom illustrates a debate common to many contemporary households, as Dre (Anthony Anderson) clashes with son Junior (Marcus Scribner) over the most effective ways to protest in social-media-driven 2020. On the school front, Jack (Miles Brown) resents how his twin Diane (Marsai Martin) is fitting in so well with the older kids.

Inside Thursday TV: Things get tricky for Massimo (Alessandro Borghi) on The CW’s Devils (8/7c) when his boss, Dominic (Patrick Dempsey), asks him to track down his missing wife, Nina (Kasia Smutniak), with whom Massimo had a torrid fling years earlier… It’s down to the (high) wire in the two-hour finale of NBC’s American Ninja Warrior (9/8c), as the remaining contestants take on a 10-obstacle course inside The Dome at America’s Center in St. Louis, with the top eight facing off in a playoff bracket as they race to the Power Tower for a $100,000 grand prize… ABC’s The Con (10/9c) profiles Anthony Gignac, who was conducting the perfect swindle as a phony Saudi prince living the high life in Miami — until he mistakenly ate prosciutto (a culinary faux pas in Muslim circles) in public.