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A.G.R.Castle

A.G.R. Castle · Science fiction

Science fiction
you can fall into.

Adventure, thrillers and hard SF with real science and people worth rooting for. No glossary. No homework. Just a story that will not let you go.

FOR READERS OF ANDY WEIR · A.G. RIDDLE · THE EXPANSE
The Magpie — cover
Coming soon

Book one · The Magpie

The Magpie

A Deepwater Portal Thriller (The Magpie, Book 1)

Getting in is the easy part.

1981. Tyler-James Porter runs the best salvage crew money keeps just out of reach: a navigator who thinks too fast for his own good, an archaeologist who reads seven languages, a financier you never turn your back on, and an exiled Soviet diver who can put any boat anywhere it shouldn't be. Their next job is a fortune in Soviet gold, lost somewhere in the warm dark of the Indo-Pacific.

The wreck should be on the bottom, exactly where every chart says it went down.

It isn't there. It didn't sink.

Sixty meters down, in water the maps have quietly learned to avoid, Porter's crew finds out what really became of a century of ships that vanished in these waters — and the door they all went through.

Crossing it costs nothing. That's the trap.

Now there's a fortune waiting on the other side, a rival closing in who wants it just as badly, and one truth the whole crew is trying not to say out loud: plenty of people have found the way in.

Almost no one has ever found the way back.

Kindle & Kindle Unlimited · coming soon Get an advance copy

Grounded adventure sci-fi with a wry voice and a pulse. If that's your shelf, pull up a chair.

The worlds

Big places. Human-sized stories.

AdventureSomewhere far, a problem to solve, a crew you would follow anywhere.
MysteryA door that should not exist. Clues that play fair. You get to solve it too.
Hard SFThe science holds if you check. You never have to.

Easy to fall into

Clear, human stories you drop straight into from the first page. No warm-up, no map of the galaxy.

People before tech

The worlds hold together, but the heart is the crew: clever, funny, a little out of their depth.

Made to be devoured

Short chapters, real momentum, dry humor. One chapter becomes two in the morning.

About

Why I write this stuff

Hi, I'm Castle. I write science fiction to be enjoyed. The best feeling I know is handing someone a book and getting the 2am text: I meant to read one chapter, I hate you, send the next one.

I'm a pantser and a tinkerer. I drop a good person into an impossible situation and find out who they are by writing toward it. I love taking ideas apart, which is why the science in my books holds up if you go looking, and why you never have to.

I've lived in Japan for twenty years. The people in that photo are my family, and they're behind most of the good decisions I've made. About the initials: they're real, they're mine, and I'm never going to tell you what they stand for.

How these books are made
  • Story, characters and direction: A.G.R. Castle
  • Brainstorming and story boards: Miro
  • First drafts: AI-assisted, then rewritten and edited line by line by the author
  • Editing, fact-checking and proofreading: A.G.R. Castle
  • Audiobook narration: a digital voice, directed and cut by the author
  • Cover and artwork: AI-assisted, art-directed by the author

Come say hi: [email protected]. I read every message.

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