Just a few miles off the Thailand coast, the island of Kothau looks like a postcard.

I'd underneath the surface lies something sinister.

In the last 20 years dozens of tourists have died mysteriously on the island.

A dark cloud who's come over the island, death, mystery and danger.

Listen to Death Island every Wednesday on the I Heart Radio app, Apple Podcasts or wherever you get your podcasts.

Paper Ghosts is a production of I Heart Radio.

Throughout the decades I've been covering true crime I've looked into more than a hundred missing persons in murder cases.

I've interviewed scores of law enforcement, victims families, even killers themselves.

All to gain a better understanding of how investigations are handled and the tools law enforcement use to develop information and solve crimes.

Much has changed over the years, but in the past decade or so I've witnessed a major shift, one that I hadn't anticipated.

The emergence of a new group of investigators.

Citizensloose. And nowhere is that phenomenon more obvious than in Tammy's Awikis case.

There was all kinds of stories, you know, you'd read that she was picked up by a stranger.

And some guy in a truck stopped to help her. Another guy in a pickup truck.

Patrick Jones is the founder of the Who Killed Tammy's Awikis Facebook group.

A passionate collection of Tammy's friends, family members, true crime buffs and citizen investigators.

Now the Facebook page grew like you wouldn't believe I mean.

I was hoping, oh maybe we'll get a hundred people, 200 people.

I think today I'm trying to look at it right now.

We've got over 4,000 members on there.

Patrick started the Facebook group in 2009. He didn't know Tammy but was drawn to her story.

Sometimes he had a picture of Tammy on the front page. And I looked at her and I was thinking I got a daughter about the same age.

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