Hello and welcome to our bookcase!

If you don't know us yet ... we are Bert Holtes & Wop Sietsma, from the Netherlands.

Let's get straight to the point, which is ...
We have been able to add a very special edition to our bookcase.

A book we wrote ourselves!

After a long time of writing and research, we managed to publish our first book under our own management in 2018.

As part of the trilogy "BACK-UP," our second book was added to the collection in 2020.

The third and final volume was published in 2023, concluding the mini-series.

To get everyone acquainted with our story, we have an ongoing giveaway campaign.

The e-books of part 1 and part 2, including the Dutch and German versions, are free for everyone to download, read and give away as gifts.

If you enjoyed our story and want to know how it ends, you can buy Part 3 for € 2.99 (or the equivalent in your currency) from various online stores.


Our story is written as a suspenseful thriller, packed with extras to enchant readers.

Whether you are an experienced thriller lover or just want to broaden your reading horizons, our trilogy has something for everyone.

We let you discover mysteries, enjoy the action and get to know special places.

We'll take you on a breathtaking journey through time and let you root for the compelling characters as they face unexpected twists and revelations you never see coming.

We'll make your heart beat faster as you shudder with repulsive characters we bring to life. But we go beyond that; and provide emotional passages that will touch you to the bone.

We will surprise you with an amazing, exciting and fascinating story.

We will take you on an adventurousjourney in which we will unravel man's most important mystery. Diveinto this intriguing story and discover the secrets that have hauntedmankind for centuries.

According to many readers, our trilogy was a thrilling reading experience and you could hardly put the book down....

If you want to experience the same, download the e-books and start reading soon.

Enjoy reading!

Why we publish the books ourselves ...

Hundreds of English-language books are being published every day.

This is a very small part of the total amount of manuscripts that publishers receive.

It is understandable that publishers need a lot of time to separate the wheat from the chaff.

That is why we decided to skip this long and uncertain process and develop and publish the book entirely independently.

and why is the eBook free!*

You need to let people know that you have written a book, and for that, advertising is indispensable.

Therefore we decided to offer the eBook of part 1 and part 2 for free* as a promotion. This way people can easily obtain the eBook and give it to someone as a gift.

Of course, for the best distribution, you need satisfied readers.

We depend on word of mouth and ask you to bring our book to the attention of everyone you have contact with.

If you want to help us, all you have to do is give away the eBooks, or forward the link from our website.

Because ... after all,

what's more fun than giving a gift!

< >

If you are curious about the covers of the books, click on the books to see the full cover.


We publish our book through various distribution options.

Through our website, internet stores, bookstores and of course with the help of readers who give away our free e-book* as a gift.

There is something for everyone.

The eBook for the digital reader, easy to take with you on vacation.

The Paperback for the reader who wants a paper book in their hands.

< >

Curious about the books?

Click on the buttons!