The real-life arrest of Robert Durst heightened the drama of the HBO documentary series "The Jinx: The Life and Deaths of Robert Durst" final episode, reports Variety.

The six-part series investigates the dark, twisted history of Durst, an heir to one of New York's most distinguished real estate dynasties. In the past three decades, Durst has been suspected of committing three murders: his first wife who disappeared in 1982, his friend Susan Berman in 2000, and a neighbor who was shot and dismembered in 2001.

In "The Jinx" finale "Chapter 6: What the Hell Did I Do?" filmmakers Andrew Jarecki and Marc Smerling play a cat-and-mouse game with Durst as they attempt to pin him down for a final interview where they present powerful evidence connecting him to the 2000 murder of Berman.

Durst agrees to the interview. Jarecki shows him a note that tipped off Beverly Hills police to Berman's murder -- a note that in last week's episode a forensic document analyst confirmed was written by Durst.

Although clearly uncomfortable, Durst denies writing the note. The interview ends. Jarecki and Durst shake hands. Durst excuses himself to the bathroom with microphone still in place and recording.

"There it is. You're caught," Durst says to himself in the bathroom. "What a disaster."

Moments later, he is recorded saying: "He was right, I was wrong" -- referring to the advice his lawyer, Chip Lewis, gave earlier in the episode that his participation in "Jinx" could bring legal consequences.

"What the hell did I do?" Durst says. "Killed them all, of course."

According to the New York Times, Jarecki and Smerling didn't realize they had the audio recording of Durst's comments in the bathroom until two years after the interview.

Durst was arrested on Saturday at a Marriott on Canal Street in New Orleans in connection with Berman's death, reports the Times. He was checked into the hotel using an alias.

Westchester, New York authorities are still investigating Durst in his wife's case, according to the Times.