The captivating case at the centre of popular podcast Serial perplexed, frustrated and intrigued listeners right up until the show’s finale episode.

One of the more mysterious figures discussed by host Sarah Koenig was Jay Wilds, close friend of murder suspect Adnan Syed and a key witness in the 1999 case.

The tight-lipped ex-drug dealer refused to speak to Koenig for the hugely successful series, but it was his testimony that essentially sealed the fate of Syed, who is currently serving a life sentence for the crime.

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Finally, Wilds has broken his silence in an exclusive interview with The Intercept, in which he stands by his testimony.

In the interview, Wilds describes the controversial Syed as a “pompous, arrogant, driven” young man who was unable to cope with his first breakup.

“I don’t necessarily know if he meant to kill Hae before he did it or if it was a sudden moment thing, but looking at his life, from what I saw, he seemed to be far out of his realm when it came to Hae leaving him,” Wilds says.

“From the way he carried himself, at least, it looked like he had never lost anything before. And it was really hard for him to deal with being on the losing end.

“In that situation, he was the loser. And people were starting to find out he was a loser, ‘Oh, you and Hae aren’t together anymore. She got a new boyfriend?’ And he didn’t know how to deal with that.”

Wilds, who is now a father, felt he was unfairly depicted by Koenig in the series and reiterates he never had a “real friendship” with Syed, saying “he didn’t call me unless he needed something”.

When the murder first came to the attention of the police back in February 1999, the then 19-year-old refused to cooperate with police, a fact many podcast listeners held against him years later.

Speaking to The Intercept, Wilds blames his apprehension on his drug dealing.

“It wasn’t just like I was selling a nickel bag here and there. At the time, this was Maryland in the ’90s, the drug laws were extremely serious,” Wilds says.

“I also ran the operation out of my grandmother’s house and that also put my family at risk. I had a lot more on the line than just a few bags of weed.”

The interview, which is the first in a two-part feature, also covers the gruesome details of the burial of Hae’s body, which Wilds has admitted to assisting.

Wilds explains his decision to help Syed was dictated by his fear Syed would turn him into the police for drug dealing.

“Adnan says, ‘Just help me dig the hole.’ And I’m still thinking, ‘Inner-city black guy, selling pot to high school kids.’ The cops are going to fry me,” Wilds says, before explaining that he didn’t touch the body.

“We dig for about 40 minutes and we dig and dig, and he’s digging less and less. And at a certain point I say, ‘Well f**k, I’m finished. I’m f**king done.’ And Adnan’s like, ‘Oh, well, you’re not going to help me move her are you?’ And I’m like ‘No, I’m not gonna help you move her.’”

According to The Intercept, the second half of the interview will address the impact of Serial on Wilds’ life.