THEY CALLED HIM MOSTLY HARMLESS on Max is an HBO true-crime documentary where we see Internet sleuths solve a mystery. It’s fascinating and definitely worth your time. Read our full They Called Him Mostly Harmless documentary review here!

THEY CALLED HIM MOSTLY HARMLESS is a new HBO true-crime documentary on Max. In this documentary, you’ll experience the process of how Internet sleuths came together to solve a mystery. A dead person is discovered in Florida but has no ID or even a phone with him.

Who is he? That’s what the Internet sleuths want to find out to help the police. In terms of storytelling, it’s engaging, intriguing, and extremely fascinating. Yes, even the drama among sleuths as this is a detail most people who ever engage on social media will recognize.

Finding out his real name and identity is only the first step. The next is to find out who he was as a person. Well, not entirely harmless, but then, he never claimed he was with the trail name of “Mostly Harmless”.

Continue reading our They Called Him Mostly Harmless documentary review below. Find it on Max from February 8, 2024.

What’s in a trail name?

While you can change your name and use nicknames or aliases, we all have identifiers attached to us. Whether an actual ID, a credit card, or even a phone that offers either social media or a phone number that could connect to a name.

Well, usually, but not always.

These days, it takes quite a lot to go truly off the grid to the extent that you can’t be identified. And yet, it does happen as it’s the case with the individual in this John Doe case. The Collier County’s Sheriff has an emaciated victim found dead in a tent. He was only 85 pounds and surrounded by food and cash, but no ID or other identifiers.

However, it seems he was a hiker, so once Internet sleuths become involved, the hiker community is quick with clues. It turns out many people had met this man before he ended up dead in his tent – seemingly, I might add, having died without any foul play involved.

The unidentified hiker was found deceased in the Florida wilderness, but hikers from all along the Appalachian Trail have come across him in the previous months. The problem is that most only knew him by “Mostly Harmless” which was his trail name. Some also knew him by “Denim” which was another trail name!

They Called Him Mostly Harmless – Review | HBO True-crime doc

Internet sleuths to the rescue

Just as we saw in Don’t F*ck with Cats: Hunting an Internet Killer, Internet sleuths can actually break a case. In They Called Him Mostly Harmless, we also see the darker side of this. Not Internet sleuths in particular, but the dark side of social media, which we all know.

While I will acknowledge that all these Internet sleuths are giving precious and all-important time, energy, and resources to cracking the case, they come with different motivations.

For some, it’s about being the one who cracks the case. Also, having “power and control” (she says this directly, so you’ll know who I refer to) of the Facebook groups, they moderate. For others, it’s about doing what they can to help crack the case. The latter is far more noble, and the two women are as different as can be!

This is also why it’s called a “character-centric reimagining of a classic true crime genre”. Between the many hikers and Internet sleuths, we come across many intriguing and interesting people. In so many ways, it does become a case of finding yourself while trying to find someone else.

Do they find out who “Mostly Harmless” was?

Yes, we do get the identity of the person featured in They Called Him Mostly Harmless.

Turns out, it did take a village [of Internet sleuths] and a company working with groundbreaking DNA technology to crack the case, but they do. It took two years, thousands of devoted internet sleuths (some extremely devoted), and the miracle of science to identify him.

However, it isn’t just his name that’s interesting but rather how they finally found out what it was. To me, the truly interesting part is we then also get to hear from people who knew him before he became the man they called “Mostly Harmless”.

The name, it turns out, is quite accurate and one he gave himself for a reason. After all, as stated by someone else in the documentary, if you’re “mostly” harmless, you’re also partly harmful. And he was!

Watch They Called Him Mostly Harmless on Max now!

The director of They Called Him Mostly Harmless is Patricia E. Gillespie. She previously directed the true crime documentary The Fire That Took Her covering the case of Judy Malinowski. She was a young woman set on fire by a man she had dated.

Judy Malinowski ultimately passed away from her injuries but her recorded testimony was used at the trial against him. In essence, she helped convict her murderer. That’s one powerful story that you’ll want to check out as well.

In They Called Him Mostly Harmless, it’s almost the opposite case; A man passes away and has removed all identifying details. Instead of helping after his death, he left people to struggle to find out who he was. Obviously, he never asked anyone to do this, and the question becomes: Why?

After all, there’s a need to find out who any dead person was. First, due to possible criminal actions, and second to inform relatives of the departed.

The runtime of this HBO Max Original documentary is just 1 hour and 28 minutes, which makes for strong and tight storytelling. You’ll want to check it out on Max now.

HBO will release They Called Him Mostly Harmless on Max on February 8, 2024.


Collier County’s Sheriff knows this isn’t like other Doe cases — an emaciated victim found dead in a tent, surrounded by food and cash, but no ID. Stumped, police rely on sleuths around the globe to identify the man who tried to erase his own identity.

I write reviews and recaps on Heaven of Horror. And yes, it does happen that I find myself screaming, when watching a good horror movie. I love psychological horror, survival horror and kick-ass women. Also, I have a huge soft spot for a good horror-comedy. Oh yeah, and I absolutely HATE when animals are harmed in movies, so I will immediately think less of any movie, where animals are harmed for entertainment (even if the animals are just really good actors). Fortunately, horror doesn't use this nearly as much as comedy. And people assume horror lovers are the messed up ones. Go figure!
Karina "ScreamQueen" Adelgaard
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