thriller

The Witness Files

Every word she translates is evidence.

  • Complete · checked Oct 2026
  • 3 books

Start with Book 1Already reading? Find your place

About the series

Kateryna Holub is a forensic interpreter in wartime Ukraine, called in to say who is speaking on recordings of attacks on civilians. She has one rule: she never changes a word she translates. The series follows the cases where a trained ear and exactness are all she has.

At a glance

Genre
Thriller
Mood
Tense
Setting and era
Present day
Pace
Medium
Point of view
First person
Reading order
Read in order
Heat
Sweet

The books in order

3 books

  1. Book 1Start here

    The Quiet Sky

    A drone strike kills a nurse in Kherson, and the video turns up online with a laughing voice on top. Interpreter Kateryna Holub has ten days to prove who that voice belongs to, armed with a trained ear and one rule: never change what someone said.

  2. Book 2

    The Still Line

    A Russian defector reaches a forward outpost with a drive full of evidence of war crimes, and Kateryna Holub hears two voices in his testimony, one of them rehearsed. One document in the pile does not belong, and she has to prove it before the case closes.

  3. Book 3

    The Last Frequency

    Hundreds of intercepted Russian communications reach the Documentation Mission, and about one in five is fake. Kateryna Holub, now training new interpreters, must sort real from forged before an ICC deadline, against a forger who knows her methods.

Where are you in the series?

Each stop is its own page. Bookmark yours; we save nothing.

  1. Nothing yet: start with Book 1
  2. Book 1

    The Quiet Sky

    A drone strike kills a nurse in Kherson, and the video turns up online with a laughing voice on top. Interpreter Kateryna Holub has ten days to prove who that voice belongs to, armed with a trained ear and one rule: never change what someone said.

  3. Book 2

    The Still Line

    A Russian defector reaches a forward outpost with a drive full of evidence of war crimes, and Kateryna Holub hears two voices in his testimony, one of them rehearsed. One document in the pile does not belong, and she has to prove it before the case closes.

  4. Book 3

    The Last Frequency

    Hundreds of intercepted Russian communications reach the Documentation Mission, and about one in five is fake. Kateryna Holub, now training new interpreters, must sort real from forged before an ICC deadline, against a forger who knows her methods.

Get the series

  1. Book 1The Quiet Sky

    • E-book

      Coming soon

    • Paperback

      Coming soon

  2. Book 2The Still Line

    • E-book

      Coming soon

    • Paperback

      Coming soon

  3. Book 3The Last Frequency

    • E-book

      Coming soon

    • Paperback

      Coming soon

Questions

Do I have to read the books in order?

Yes. Each book gives away how the earlier ones end, so read them in the order they are listed.

Where do I start?

With Book 1, The Quiet Sky.

How many books are there?

The series has 3 books. It is complete.

About E. J. Hartley

E. J. Hartley writes mysteries and thrillers in which the murder weapon is a sentence. Hartley’s narrators are interpreters, bound by a professional rule that reads like a moral one — you do not change what is said — and every book asks what that rule costs when the accurate rendering protects the guilty, or gets somebody killed.

All books by E. J. Hartley