“Holliday is excellent at creating an atmosphere of unease.” —The Sun

“A clever slice of dystopian darkness.” —Heat Magazine

“Utterly gripping…” —C.L. Taylor, author of Sleep

“I love a book which centers around a moral dilemma, but Substitute brought so much more to the table. It's a real twisting of genres that will blow your mind.” —Caroline Mitchell, author of the DI Amy Winter series

“Original, fast-paced, and thought-provoking, this speculative thriller from the peerless imagination of Susi Holliday will keep you hooked from page one. Who would you substitute…?” —Amanda Jennings, author of In Her Wake

“Tense, gripping, and terrifyingly plausible, Substitute marries an intriguing high-concept premise with warm storytelling and the most accurate parent-child relationship since The Whisper Man.” —Ed James, author of the Cullen and Bain Scottish Crime Thrillers series

“A razor-sharp story that refuses to let you go.” —Quentin Bates, author of the Officer Gunnhilder series

“When faced with an impossible choice of who lives and who dies, a mother is caught in a twisty science of the future. I could barely breathe when reading this. Gripping!” —Rachael Blok, author of Into the Fire

“If you like chills and thrills with a dark science twist and a big hook, it’ll be right up your street. There is no substitute for Holliday…” —Mason Cross, author of the Carter Blake series

“Absolutely loved Substitute. It poses a fascinating question I can’t stop thinking about: if you could save the lives of three loved ones by choosing three others to die in their place, who would they be? Not a wasted word and so compelling.” —Fiona Cummins, author of When I Was Ten

“Its future-possible plot and richly drawn characters kept me hooked from start to finish. Easy to devour and hard to forget.” —John Marrs, author of What Lies Between Us

“Dark, clever, and thought-provoking, just as you’d expect from Holliday. She puts everyday people through not-at-all everyday situations, and you, the reader, have to watch it all fall apart with your heart in your throat.” —Louise Beech, author of This Is How We Are Human

“Loved it. Could you sentence someone to death to save a loved one? A thrilling speculative thriller for fans of Blake Crouch and John Marrs.” —Mark Edwards, author of The Hollows

“I always get excited when a new Susi Holliday book comes out and Substitute didn’t disappoint. A wild ride and a highly original story you won’t want to miss.” —C S Green, author of Sleep Tight

“Wowzers—I’ve just finished reading a proof of Susi Holliday’s twisty-turny thriller Substitute and it’s epic!! Mind-bending, pulse-pounding, techno-thriller brilliance! Perfect for fans of John Marrs’s The One, JP Delaney, Blake Crouch.” —Steph Broadribb, author of Deep Down Dead

“What an absolute belter of a book. I’m loving the slight Sci-Fi edge that her work is taking lately, while still remaining effortlessly cool and relevant. Each new book surpasses the previous, something I thought impossible. Holliday is one of the most exciting authors I’ve come across.” —JM Hewitt, author of The Life She Wants

“Susi Holliday knocks it out of the park with this book. It’s everything you want in a thriller—imaginative, credible, and engaging; rocketing relentlessly towards a gut-wrenching conclusion as the stakes grow higher and higher…Brilliant.” —Louise Voss, author of The Last Stage

“Absolutely loved it! Original and compelling, with a killer premise and gut-wrenching dilemmas. And I do love a rogue scientist.” —Roz Watkins, author of the DI Meg Dalton thriller series

“A chilling and addictive tale of the price of good intentions, devastating choices, and science gone wrong. Frankenstein meets The Chain in Susi’s most powerful thriller yet.” —Heleen Kist, author of Stay Mad, Sweetheart

“A cracking premise. If you want something a little different then I suggest you check this out. Read the blurb. Go on. You won’t be able to look away!” —Rebecca Bradley, author of the DI Hannah Robbins series

“A twisty, super creepy tale that kept me turning the pages well into the night—be careful what you wish for!” —Emma Haughton, author of The Dark

“Deliciously disturbing, thought-provoking, and unforgettable. Everything I want in a thriller.” —Jo Jakeman, author of Safe House

“If you’re looking for a pacy, smart, and twisty plot, Substitute is an absolute must read. This is a book that feels terrifyingly real.” —Lisa Cutts, author of Don’t Trust Him

“You’d be mad to substitute Susi Holliday’s clever, complex & compelling thriller for anyone else’s: who lives and who dies?” —Claire Seeber, author of The Street Party

“Wow! Creepy, compelling, and so thought-provoking! Who would be your three?!” —Karen Cole, author of Deliver Me

Susi Holliday grew up near Edinburgh and worked in the pharmaceutical industry for many years before she started writing. A life-long fan of crime and horror, her short stories have been published in various places, and she was shortlisted for the inaugural CWA Margery Allingham Prize. She is the bestselling author of eight novels and a novella, several of them written as SJI Holliday. Along with three other female authors, she provides coaching for new crime writers via www.crimefictioncoach.com. You can find out more at her website, www.susiholliday.com, on Facebook at www.facebook.com/SJIHolliday, on Twitter @SJIHolliday, and on Instagram @susijholliday.