What to Watch on Sunday: ‘Piketon Family Murders’ on Oxygen, ‘Veep’ returns on HBO

The Piketon Family Murders (7 p.m., Oxygen) - Oxygen’s two-hour special examines the headline-grabbing, execution-style murder of a family of eight in Piketon, Ohio, in 2016. It would take two years for arrests in the Rhoden Family murder case to be made, meanwhile suspicions and rumors tore the small town apart.

NCAA Tournament (CBS, TBS, TNT, truTV) - The Elite Eight games of the 2019 NCAA basketball tournament continue today, with games on CBS. Duke plays Michigan at 5 p.m. We have your complete viewing guide here, with the schedule, channels and streaming options.

Mrs. Wilson (9 p.m., PBS / UNC-TV) - Ruth Wilson (“Luther”) stars as her grandmother Alison in this three-hour miniseries based on the true story of Alison’s complicated marriage to MI-5 operative and popular spy novelist Alexander Wilson (Iain Glen, “Game of Thrones”). Part 2 airs April 7.

The Walking Dead (9 p.m., AMC) - In the aftermath of an overwhelming loss, the group must endure a ferocious blizzard.

The Case Against Adnan Syed (9 p.m., HBO) - In the final episode, Adnan has been granted a new trial but must contend with the state’s appeals, and then with the Court of Appeals reversing both lower court decisions granting Adnan a new trial.

Barry (10 p.m., HBO) - In the Season 2 premeire, Barry tries to convince Sally and the rest of the class to go ahead with a performance, despite the absence of teacher Gene.

Veep (10:30 p.m., HBO) - The seven-episode seventh (and final) season starts with Selina Meyer (Julia Louis-Dreyfus) looking to get back to the Oval Office.

Some programming descriptions are provided by networks.