Many of us avoid thinking about death, but not Keanu Reeves.

"I'm 59, so I'm thinking about death all the time," the Hollywood megastar has revealed to BBC News.

That's a good thing, he adds.

"Hopefully it's not crippling, but hopefully it's sensitised [us] to an appreciation of the breath we have, and the relationships that we have the potential to have."

The reason we're sitting with The Matrix star, ruminating on life and mortality, is not because he has another blockbuster to promote.

This time, it's a new book - Reeves' first novel.

The Book of Elsewhere, written in collaboration with British science fiction author China Miéville, follows an immortal warrior, who wants to be able to die.

We meet Reeves and Miéville in a lowly lit hotel bar in central London.

The Canadian actor, who is based in Hollywood, makes time to see us in between gigs with his Dogstar band.

The night before, the band played in Manchester. Reeves looks a bit tired as we begin the 30 minute interview.

But his passion for his novel also comes through strongly.

The Book of Elsewhere is based on the hugely successful BRZRKR comic book series created by Reeves.

Released in 2021, BRZRKR - pronounced "berserker" for the uninitiated - is also due to be adapted into a live-action Netflix film starring Reeves, as well as an anime series.

For Reeves, comic books have a special appeal.

"I love the images," he said. "I love words and storytelling and I love the way that you can have this engagement that overlays. And so you can look at the art and then you can follow the story."

The actor plays down his role in the collaborative process though, insisting: "I didn't write a novel. China wrote a novel."

Miéville argues "that's putting it too far," adding: "It wouldn't exist in the form without a lot of very thoughtful and careful work with Keanu."

The central character in the plot is known only as "B".

With his long dark hair, B shares physical similarities with Reeves.

And when the comic book first came out, some fans also pointed out certain thematic similarities between the two, including a difficult personal life.

Reeves has lost several people he has loved in his life, including his girlfriend, their stillborn daughter and his best friend.

But that might be where the similarities end.

B is 80,000 years old, half-mortal and half-god. He also has a "curse of violence", which seems completely unlike Reeves.

The actor, who is known for his gentle, mild-mannered persona, has often been described as the nicest man in Hollywood.

B, on the other hand, is someone who can "punch through people's chests and rip their arms off, rip their heads off", according to Reeves.

So where does such violence come from?

"I think it was influenced by some of the action films that I had done," said Reeves, who has also starred in the Speed and John Wick franchises.

Reviews of the comic book were broadly positive when it came out, so Reeves and Miéville will be hoping to replicate that success.

In Flickering Myth, Calum Petrie awarded it seven out of 10 stars, writing that it was "enjoyable" but also "a bit more on the gory side than I am used to in a lot of comics".

It was given 9.5 stars by Justin Harrison in AIPT Comics, who praised it as "excellent" and "intriguing" while also cautioning readers about the violence it depicts.

There's no doubt that this book is violent. In its opening pages, it describes a shooting, followed by "the tough bloody business of the clean-up".

We asked Reeves about the much debated link between violence on-screen and in books, and in the real world.

Momentarily, he appears defensive.

"I hope if they read BRZRKR, that they don't go out and start ripping people's arms off and chopping their heads off," he said.

"Because there's also a love story in it. But if you do read it, I hope maybe you can find love if you don't have it."

Miéville also pushed back against there being a connection between depicted violence and real violence.

"I get quite irritated about how this question is posed," he said.

"It's so clearly a kind of cultural scapegoating," he added. "I think the idea of looking at video games and movies and so on, it's just a way of exonerating the people who are really profiting from the violence."

Having created a whole fantasy world, you wonder whether Reeves is trying to escape from reality.

"Maybe ultimately the fantasy of building another world brings some kind of comfort in some way," he admits.

"There's something ultimately about the creative gesture that comes from pain," he added.

"Creating stuff is great. Just creating, sharing, and hopefully people like the stories that we tell."

And if they do - if the book is a success - what will Reeves do with the proceeds of the book?

The actor is famed for his generosity, and a lot has been written about how he reportedly doesn't like owning things.

But this, too, is something Reeves appears to push back on, as our interview comes to a close.

"I love owning things, I love having stuff," he said.

"I'm certainly not going to present myself as someone who gives everything away."

The Book of Elsewhere is published on 23 July by Penguin.