I'm always a fan of a film that reminds me why I'm a reporter - but I never expected one would be about a murdered friend.

Lyra McKee was killed on the streets of Derry in 2019 - almost on the anniversary of the Good Friday Agreement.

Since then the loss hasn't eased for her family and friends. And neither has the anger that was on raw public display at her funeral in Belfast.

Attended by politicians of all stripes, they were rightly called out for only coming together after the murder of a 29-year-old woman.

And that moment, the anger, reaches through the screen in the documentary about her life, Lyra.

Directed by Alison Millar, it is very much a collaboration with Lyra's family and friends. Lyra's award-winning words are heard and seen throughout this film, as are pictures and home videos of her.

This is a film about Lyra's life and loves - of journalism, of her partner, of her family. That makes the loss worse because you come away asking, as we all should, "why?"

The documentary aired at random and awkward times for a week in Glasgow in December - but is finally getting a deserved prime-time debut on Channel 4 next week.

Reporters study grief. We ask questions about the grief of others, trying to unpick how others express the inexpressible. We could write hundreds of articles about it. Lyra could write thousands more.

I can't express my personal grief for Lyra's loss. I don't remember when I first emailed her many years ago, but I found her as a kindred spirit over the internet.

Journalism might look like a busy team office on film, but it's isolating. Lyra and I both went through moments of doubting how to pay the bills while we kept pushing to do reporting we were passionate about.

I am grateful Lyra kept going. Though she is gone and gone too soon, the documentary about her life is a celebration of what she achieved, and what she was capable of.

And it is about what robbed her of that capability: the violence and division that she grew up in the middle of, even as the great and good abroad congradulate themselves on a peace deal that still left many people - especially "ceasefire babies" dying, but through hopelessness and despair.

Lyra was a fiercely proud reporter, and fiercely passionate local reporter in Northern Ireland.

I emailed her - of course about journalism - three days before she died. The news story the morning after and the moment of realisation still feels unreal.

And I say that as someone who only got to meet her in person once. I went up to her at a journalism conference and introduced myself and she flung her arms around me for a hug. I'd give anything to have been able to work with her or share chats about, well, anything.

In that funeral moment, the priest asked "why". That was Lyra's favourite question when she was little. Instead of "mummy", it was "why".

Why.

Lyra airs on Channel 4 on Saturday, April 15 at 9.25pm.