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Here’s what’s on TV tonight.

20/20: The Case of the Killer Clown (9 p.m., ABC)

Correspondent Deborah Roberts reports on the case of a Florida mother murdered in cold blood 30 years ago by a clown. Marlene Warren was killed in May 1990 by a clown carrying balloons and flowers who walked up to her front door and shot the 40 year old at point-blank range. The murder rocked the affluent Florida suburb where Warren lived, and friends and family were instantly suspicious of her husband, Michael Warren. But Michael had an airtight alibi, so it took investigators 33 years to solve the case.

Two weeks ago, on April 25, Michael’s second wife, Sheila Keen-Warren, pleaded guilty to second-degree murder.

Roberts has an exclusive interview with the victim’s son, Joe Ahrens, who talks about how his mother was killed and how her murder has impacted his life. There’s also an exclusive interview with Keen-Warren’s attorney, Greg Rosenfeld, as well as interviews with prosecutors, witnesses, and other family members of the victim.

To stream: This streams the next day on Hulu.

Dateline: Killing Time (9 p.m., NBC)

Keith Morrison reports on the August 1997 murder of high school student Ricky Cowles Jr., in Lancaster, California. Ricky was found lying in a pool of blood in his apartment, and his friends, including Amy Preasmyer, called 911. Police made an arrest months later, but the family believed there was more to the story.

The episode features an exclusive interview with convicted killer Billy Hoffman, who talks about what happened that night and why he killed Cowles. Also interviews with the parents Ricky Cowles and Amy Preasmyer, as well as detectives.

Elton John Live: Farewell From Dodger Stadium (Disney+)

This Elton John concert is the next-best thing to being there. The Los Angeles concert experience features special guests, with John performing his biggest hits.

Some programming descriptions are provided by networks.