Double fault

Serena Williams’ skirmish with umpire Carlos Ramos wasn’t a high point of the tennis superstar’s career. But the infamous incident from the 2018 U.S. Open final is the ideal subject to kick off the new docu-series “Backstory,” an offshoot of ESPN’s wildly successful “30 for 30” franchise. Future topics include the downfall of “Shoeless” Joe Jackson and how former Notre Dame linebacker Manti Te’o got pulled into an online hoax.

Noon Sunday, KSTP, Ch. 5

The outsider

“I Am Patrick Swayze” spotlights some of the late actor’s most celebrated films, including “Ghost” and “Dirty Dancing.” But the documentary is just as interested in proving Swayze was even more macho in real life than he was on the screen, taking blows to the ribs during “Road House” fight scenes and jumping out of planes for “Point Break.” Demi Moore and Minnesotan Kelly Lynch are among those still in awe.

8 p.m. Sunday, Paramount

Abbey road

The classes unite for “Downton Abbey Live!” This Q&A with key cast members promises to reveal behind-the-scenes stories from the hit series as well as offering teasers for the feature film, set to be released Sept. 20.

8 p.m. Sunday, TPT, Ch. 2

Bully pulpit

Danny McBride’s love affair with dimwitted protagonists continues with “The Righteous Gemstones,” a dramedy about a televangelist who breaks most of the commandments after he’s blackmailed by hillbilly crooks. The series is more polished than McBride’s last effort, “Vice Principals,” but you’ll spend so much time marveling at co-star John Goodman’s recent weight loss, you may not even notice.

9 p.m. Sunday, HBO

Neal Justin