"Why you need to watch Dear Zachary - the single best documentary of all time."

What I am about to share is not simply a throwaway recommendation.

It’s not just a “… oh if you’re bored this weekend check out this movie…” comment used to fill an awkward silence.

It’s legitimate life advice.

An order.

And once you’ve finished it, I expect a thank you letter and/or gift expressing your sincerest gratitude for the greatest doco suggestion you’ve ever received.

Monique Bowley, Jacquline Lunn and I share our recommendations on Mamamia Out Loud this week. Including my favourite documentary ever made. Post continues below. 

Now, I’ve watched a lot of documentaries in my time. Hundreds. I’ve studied documentaries. I’ve written about the best documentaries on Netflix right now, and the 11 best documentaries of all time.

In short, when it comes to the genre, I know what’s up. 

So here it is: If there’s one documentary you need to watch before you die, it’s Dear Zachary: A Letter to a Son about his Father. 

Hear me out. When I saw the title, next to a 94 per cent rating on Rotten Tomatoes, I wasn’t convinced. But here’s the plot.

A man named Andrew Bagby was dating a woman named Shirley Jane Turner. They were very happy for a period of time, before she became increasingly possessive and violent.

In 2001, Bagby decided to end their relationship.

Months later, he was murdered by Turner.

After she was arrested, it was revealed that Turner was pregnant with Bagby’s child, a boy. She decided to name him Zachary.

So documentary maker and close friend of Bagby, Kurt Kuenne, decided to make a film to give to Zachary, so he could see what an incredible man his father was.

But this would not be the end of the story.

In what is potentially the most unexpected twist in any documentary, the film becomes a true-crime masterpiece that deeply affects everyone who watches it.

Martin Tsai of the New York Sun describes the film as "a first-rate thriller...and the film is so unsettling that it will stay with viewers for a long time... It's hands down one of the most mind-blowing true-crime movies in recent memory, fiction or nonfiction."

In a climate of true-crime-mania, which routinely privileges the perpetrators over the victims, Dear Zachary never loses sight of the most fascinating character in the story; Bagby himself.

As Andrea Denhoed writes for The New Yorker, "It stays so close to Bagby and to the people who loved him that there’s never any question that it’s their side of the story being recounted... as much attention is given to the fact that he always wore shorts as to the number of times he was shot. Their pain functions as evidence as the film builds a case against the Canadian bail and extradition protocols. Even during his stilted summaries of events, you can sometimes hear Kuenne choking up..."

Dear Zachary is not about cracking a mystery, but leaves viewers with, as Denhoed argues, a "feeling of stymied sickness", which is much closer to the lived experience of a violent tragedy.

It's human. It's touching. It's terrifying.

And it's a documentary that absolutely everyone must see.

You can watch Dear Zachary on iTunes, here. 

You can listen to the full episode of this week's episode of Mamamia Out Loud, here. 

Check out all our podcasts and any books mentioned in any of our shows at apple.co/mamamia.