John Wayne meets John Wyndham. Threshold Shift by @GDTinnams



Cover links to Amazon.com

Threshold Shift



Written by G.D. Tinnams

Genre: Science Fiction, Action & Adventure


I will hurt you more than you hurt me. Death will be a long time coming.

On the frontier planet of Threshold a hard won truce exists between the native inhabitants and the human settlers. When a murder puts this truce in jeopardy, Marshal Jacob Klein must try to see justice done, whatever the cost.

But Klein has his own problems - an addiction to a fatal narcotic, a disenfranchised son, and a dark secret he has been hiding for over two decades.

For there is a greater threat to Threshold than just a petty civil war. An ancient presence has invaded the planet for its own purposes and Jacob Klein is in no shape to stop it.

Praise for

Threshold Shift


I really enjoyed reading this book.

It was exciting and action packed from start to finish, without the traditional showdown that I expected at the end. The author has taken time to come up with a clever ending that surprised me.

All in all it felt very real, and I was very interested and quite involved in how the characters got on. There were some complex relationships which developed in very interesting ways. The action scenes were good but no over zealous and it never got out of control.

Recommended for sci-fi buffs everywhere.



It's John Wayne meets John Wyndham in this debut novel of frontier colonists, aboriginal lizard-men and psychic experiments gone awry. Author G. D. Tinnams has created a remote world that attracts men with pasts, populated it with not-so-noble savages and tamed it with enigmatically archaic technology; the result is classic sci-fi Western genre fiction...until the true nature of the Marshall and his son is explored.

The author keeps a tight pace and concentrates on character. There's a refreshing absence of technobabble and an admirable economy of style. As with any story 'with a twist', the timing of the switch is crucial - and here it is finely judged. The Western tropes peak just as the reader engages with the 'twist', which works to broaden the story's scope, raise the stakes and throw new light on the key characters.



I got through this book in just a few days. It's very easy to read, and has a very tightly focused plot with action and character development in equal measure.

The style is fast, punchy. The writer is very economical with his wordage and as a result the book doesn't pause for breath until the very end.