MONSTERS INSIDE: THE 24 FACES OF BILLY MILLIGAN on Netflix is a new documentary series in the true-crime subgenre. It runs too slow but is extremely fascinating. Also, you’ll see what inspired M. Night Shyamalan’s Split. Read our full Monsters Inside: The 24 Faces of Billy Milligan review here!

MONSTERS INSIDE: THE 24 FACES OF BILLY MILLIGAN is a new Netflix docu-series. We’re in the true-crime subgenre and if both the story – and certain people involved – feel familiar, there’s probably a very natural reason: The case of Billy Milligan was a fairly big inspiration for M. Night Shyamalan’s Split starring James McAvoy.


Our review of Shyamalan’s Glass which also featured the James McAvoy character >

I found episode 1 to be very slow despite having a fascinating topic to cover. Also, the setting for most interviews seems odd – to say the least. Interviewing relevant people is always good, but placing them in strange places is distracting, which is a big no-no when dealing with documentary filmmaking. At least in my book.

Continue reading our Monsters Inside: The 24 Faces of Billy Milligan review below. There are four episodes in this docu-series and we watched them all for this review.

A very contagious diagnosis

While I did find Monsters Inside: The 24 Faces of Billy Milligan to be too slow and not very well produced or directed overall, I did enjoy many elements of it. For one, the fact that multiple personality disorder (now known as “dissociative identity disorder” or DID) suddenly became a very popular diagnosis.

Multiple personality disorder suddenly became a common diagnosis. Almost as if it became contagious for a few years after Billy Milligan’s case. I guess “getting away with murder” (yes, I am grossly oversimplifying) can do that. Also, it was popular so any doctor who wanted to make a name for themselves was eager to have one of those interesting patients.

So it seemed anyway. The fact that this was included in this Netflix docu-series was very positive.

Whether you believe in the concept of dissociative identity disorder or Billy Milligan specifically, will probably play a big part in how you view this true-crime production. However, no matter anyone’s personal feelings on this diagnosis, the case of Billy Milligan – specifically after he pleaded insanity and was acquitted – is full of many grotesque elements.

His victims certainly did not get any kind of fair treatment. Nor did anyone else who came into contact with him, since he was awarded some very strange benefits while being treated. And of course, being admitted for treatment was instead of going to prison, since there was no doubt that he did indeed rape and commit armed robbery.

Or his body certainly did, even if the mind of Billy Milligan specifically perhaps did not.

Monsters Inside: The 24 Faces of Billy Milligan – Netflix Review

The inspiration for Split

I’ll be honest and say that I didn’t actually think about the Shyamalan movie Split until Dr. Cornelia B. Wilbur appeared on the screen. The way she talked immediately reminded me of the Betty Buckley character from Split and that was when it clicked. Even though it should have been obvious from the beginning.

Watching Monsters Inside: The 24 Faces of Billy Milligan, I must admit that Betty Buckley portrayed an upgraded version of psychiatrist Dr. Cornelia B. Wilbur. While she was a trailblazer in the field of multiple personality disorder (the book Sybil is about one of her patients), she also seemed to fall prey to her own success. Her methods were definitely rather grotesque.

And yes, another Billy Milligan-inspired production is in the making. This time actually based on the book The Minds of Billy Milligan and the adaptation will be called The Crowded Room. For the record, the author of this book, Daniel Keyes, is also quite the “character” and most definitely exploited his relationship with Milligan.

Watch Monsters Inside: The 24 Faces of Billy Milligan on Netflix!

Olivier Megaton is the director of the Monsters Inside: The 24 Faces of Billy Milligan documentary series. He has done a lot of action movies in the past. Maybe that’s the reason why the interview settings are so grotesque (for lack of a better word). When the story is as fascinating, as this one truly is, then you don’t need any added “action” in terms of background noise.

Previously, Olivier Megaton directed movies like Transporter 3 (2008), Colombiana (2011), Taken 2 (2012) and Taken 3 (2014). In other words, all extremely fast-paced action movies with lots of fast cuts. This is, unfortunately, quite the issue when he then does this Billy Milligan documentary.


Our review of Olivier Megaton latest feature film The Last Days of American Crime on Netflix >

It almost feels like the subject is just another action movie rather than an in-depth documentary. The strange camera angles, distracting background, and very repetitive shots of Billy Milligan looking downright evil pull away from the main focus. Still, I am happy that I watched the entire thing because it is a fascinating story.

It’s just one that should have been told in two strong episodes rather than four weak ones. Also, the French directors need to include French “experts” that have nothing to do with this case directly. Not a good thing and yet another thing that distracted and made this a slower true-crime documentary than needed.

Monsters Inside: The 24 Faces of Billy Milligan is out on Netflix from September 22, 2021.


In 1977, a serial rapist struck Ohio State University. Overwhelming evidence quickly led investigators to Billy Milligan, an aimless young man with a traumatic childhood and a criminal record. Yet upon his arrest, Billy had no memory of the assaults, and his mannerisms seemed to change on the spot. A parade of psychiatrists diagnosed him with multiple personality disorder (now known as dissociative identity disorder), eventually determining that as many as 24 distinct “multiples” existed within his mind. In a case that captivated the nation, their analysis anchored a first-of-its-kind legal defense strategy, and Billy was found innocent by reason of insanity. His trials, however, were far from over.

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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