A nail-biting, award-winning crime novel from the author of The Echo Man! A shocking crime scene... DCI Adam Bishop has never seen anything like it. Five murder victims - all with numbers written above their bodies. And the spray-painted daubs reveal a horrific truth: the killer is counting down... A case that twists and turns... When Dr Romilly Cole learns of the murders, they trigger memories of a traumatic past she has tried hard to forget. But getting involved with the case is a bad idea. She and Bishop have history - and working together could never end well. A race against time to stop a killer... Adam and Romilly soon realise the truth lies in a decades-old case, and only Romilly holds the key. But they must act quickly, because with every passing day, there are more victims. And as the numbers edge toward zero, the murders get closer to home... The countdown has begun. Who will die next? 'The Twenty is smart and brooding, icepick-sharp and shadow-dark; best of all, though, it's scary as hell. Think you're tough? Pick up this novel and prove it' A. J. Finn, author of The Woman in the Window 'Fierce, frightening, twisted and addictive. The Twenty grips you by the throat and keeps on squeezing until the very end' Chris Whitaker, author of We Begin at the End 'Riveting reading ... Packed with suspense, it is a story that horrifies and hypnotises at the same time' Daily Mail 'Fast and furious, Sam Holland doesn't take her foot off the pedal for a second' Victoria Selman, author of Truly Darkly Deeply 'If you like crime that's dark, twisted, and keeps you up all night, Holland is the author for you' Jack Jordan, author of Do No Harm 'Really disturbing and gripping but with a trademark sexy cop at the heart to offset the serial killer gore. Lots of fun in a very nightmarish way' Harriet Tyce, author of Blood Orange * THE ECHO MAN won the Bronze Bat for Best Debut Thriller in October 2022, and THE TWENTY won the Silver Bat for best thriller of the year in October 2023, at the Netherlands Thriller Festival .