Robert Durst (courtesy of HBO)

You may have heard HBO’s documentary series “The Jinx: The Life and Deaths of Robert Durst” came to a stunning real-life conclusion this weekend: Bob Durst, the subject of the series and the real estate heir allegedly linked to three people’s deaths over multiple decades, was arrested and will be charged with the 2000 murder of his friend, Susan Berman.

[Robert Durst arrested in New Orleans on murder charges]

Durst’s arrest was right after new evidence emerged in the penultimate episode that aired last week. Filmmakers discovered that a letter Durst wrote to Berman had very similar handwriting and the same misspelling as an anonymous note sent to police that led to Berman’s body. As Durst himself put it, it was “a note to the police that only the killer could have written.” Durst has always denied having anything to do with Berman’s death.

Sunday night’s episode was the series finale (Durst’s lawyer claimed his client’s timely arrest was a publicity stunt for the show) had quite the ending. In the final scene, Durst goes into a bathroom alone with his microphone on, apparently unaware he’s still being recorded. After mumbling a lot of things to himself, he’s heard saying, “What the hell did I do? Killed them all, of course.”

[Did an HBO show solve a 14-year-old murder case?]

The whole episode focused on the scramble after the filmmakers discovered the troubling letter. Here’s how the finale played out, and below, a transcript of what led to what some interpret as an alleged confession.

* The letters

Viewers get a good look at the two letters. The first one is a short, innocuous letter to Berman from Durst. It’s is addressed in all capital block letters, and her Beverly Hills address is misspelled as “Beverley.” The second letter, an anonymous note sent to the police directing them to Berman’s body, is addressed to the “Beverley Hills Police,” in extremely similar writing and with the same misspelling.

A screenshot from Episode 5 of HBO’s “The Jinx.” Above is a copy of the letter mailed to police to tell them there was a dead body in Susan Berman’s home. Below is a letter Durst wrote to Berman nine months before she was killed.

* The importance of the word “cadaver”

The anonymous note to police simply had Berman’s address and the word “cadaver.” The film acknowledges that’s a very unusual way to describe a dead body. The filmmakers interview Eleanor Schwank, a friend of Kathie Durst, Bob’s wife who went missing in 1982. “I think that word is so telling,” Schwank says, adding that Kathie had a cadaver in medical school and talked about it all the time. “Bob heard that word over and over again in relation to a dead body.”

[HBO takes a ‘Serial’ approach in ‘The Jinx’]

* Reactions to the letter 

“Oh, Jesus,” says Jeanine Pirro, the former district attorney of Westchester County who investigated Kathie’s death. ” ‘Beverley’ … oh God, the ‘B’ is exactly the same. Son of a bitch.”

Meanwhile, Durst’s attorney Chip Lewis takes a very long pause when film director Andrew Jarecki shows him the letters. “I couldn’t help but notice a similarity between the two,” Jarecki says.

“I see similarities,” Lewis says. “And I see differences.”

* A forensic document examiner weighs in

The filmmakers gather about 40 documents written by Durst to deliver to John Osborn, a forensic document specialist who helps them figure out if the letters were written by the same people. Osborn carefully takes the audience through each step of a comparative analysis where he takes individual letters and numbers, all on documents that Durst wrote, and analyzes them for similarities. The conclusion? “I mean, I would say they’re pretty bang-on,” Osborn says, looking at multiple figures written by Durst. “These characteristics are unique to one person and only one person.”

* Andrew Jarecki’s thoughts

Jarecki has been looking into Durst’s background for years, with Durst being allegedly connected to his wife’s disappearance in 1982; Berman’s shooting in 2000; and the death of Durst’s neighbor, Morris Black. (Durst was acquitted by a jury, telling them he shot Black in self-defense.) Jarecki’s research led to a 2010 film “All Good Things,” where Gosling played a fictional character based on Durst; which could be part of the reason Durst agreed to sit for hours of interviews used during “The Jinx.” During the episode, Jarecki admits finding the striking letters were tough for him emotionally, given that he had always given Durst the benefit of the doubt. Now?

“My feelings are different,” Jarecki says. “Not because I thought, ‘Well, I was sure that Bob was innocent,’ but I wasn’t sure that Bob was guilty. And that’s a big, big change.”

* Getting Durst to sit for another interview.

Much of the episode dealt with Jarecki and crew tracking down Durst to sit down for another interview after they discovered the letters. Durst is very shifty, lying about taking a trip to Madrid and then scheduling and canceling multiple interviews. Finally, he has a phone call with Jarecki that appears to be the end.

“I sort of think you need a new gig — that you’ve done Robert Durst. I’m at the point of not doing anything. Period,” Durst says, hanging up up the phone. The filmmakers are discouraged.

Then, a break: Durst gets arrested by breaking the order of protection that required him to stay away from his estranged brother Doug’s house. Durst contacts Jarecki because his lawyers need documentary footage for his defense. Suddenly, Jarecki has leverage. And magically, Durst agrees to come in for another interview.

* The interview

The day of the interview, Jarecki is nervous — he’s never had a reason to fear Durst before, but now he could potentially become his enemy with this new evidence.

Durst shows up and everything is casual. Before he arrived, Jarecki and his fellow producers plotted about how exactly to get the best answers out of Durst: Start with softball questions about photos of him and Susan Berman, then segue into the letters.

So Durst looks at a bunch of photos, providing commentary, even asking for a copy of one of the pictures. Then Jarecki shows him the first note to Susan Berman, which read “Now and again I think about old times,” and is signed “Good luck, Bobby.”

Durst says he has no recollection of writing the note, but that it was something he could see himself doing — and that it could have had a check inside. Okay, says Jarecki —  now, he wants him to read the second envelope, the “famous” anonymous cadaver note to the police.

Durst reads the second envelope. “Same misspelling,” he notes of the “Beverley Hills” address. The camera is focused on Durst, but his expression doesn’t change. Here’s the rest of their conversation:

Jarecki: “What does that say to you?”

Durst: “Well, I mean the writing looks similar, and the spelling is the same, so I could see the conclusion the cops would draw. Or the writing exemplar person would conclude they were both written by the same person.”

Jarecki: “I guess the question is: Did you write the cadaver note?”

Durst: “No, I didn’t write [the] cadaver note.”

Jarecki: “So you wrote this (first letter) but you didn’t write this (second letter).”

Durst: “I definitely wrote this (first letter). I definitely did not write that (second letter).”

Jarecki: (pause) “I guess I’m searching for a way among other things to understand how — ”

Durst: “Two people could misspell ‘Beverly?’ ”

Jarecki: “I’m searching for a way to figure out how you didn’t write the cadaver note, ’cause it’s so similar.”

Durst: (pause) “What I see as the similarity is, really, a misspelling in the ‘Beverly.’ Other than that, the block letters are block letters. How else would you write a block letter like that? I mean, it’s almost like a typed thing. With two typewriters, it’s gonna look the same.”

Jarecki: (pause) “So you wrote one of these, but you didn’t write the other one.”

Durst: “I wrote this one, but I did not write the cadaver one.”

Jarecki: (holds up a photo of both envelopes) “Can you tell me which one you didn’t write?”

Durst: (long pause) “No.”

* “Killed them all, of course.”

That’s it — Jarecki thanks Durst for coming in and Durst leaves the room to go to the bathroom. Everyone else leaves, too, so we just see an empty conference room. Then a message comes on screen — Durst’s microphone continued to record him talking to himself while in the bathroom. Here’s what Durst says, with various groans heard in between phrases:

“There it is. You’re caught. You’re right, of course. But you can’t imagine. Arrest him. I don’t know what’s in the house. Oh, I want this. What a disaster. He was right. I was wrong. And the burping. I’m having difficulty with the question. What the hell did I do? Killed them all, of course.”

With that, the series ends. And his lawyer’s words earlier in the episode seem very prescient. Chip Lewis, the attorney, told Durst that he knew his client wanted to tell his story to the public, but it came with risks.

“You run the risk of pissing people off,” Lewis told Durst. “And people that have intentions contrary to your liberty. Don’t forget that.”