Illegals: Russia's Most Audacious Spies and the Plot to Infiltrate the West

One of the most compelling and perceptive books on intelligence of the past decade -- 'The Best Books of 2025' ― Economist

Thrilling ... grabs you by the lapels from the very first page ― Spectator

[A] gripping account of the agents who lived in the West under the deepest of covers ... Walker makes the sparkling most of an outlandish cast of characters ― Sunday Times

Engrossing ... exciting ... by turns suspenseful, funny, chilling and surprisingly poignant ― TLS

Absolutely fascinating -- Andrew Marr

Walker has unearthed some eye-popping stories to fashion this history of the weirdest and most dedicated Russian agents ... his interpretation of this remarkable story is the most sympathetic and interesting I have yet read -- Misha Glenny ― Financial Times

The strange lives of the illegals make compelling stories ... very readable -- Adam Sisman ― Observer

Filled with astonishing personal details, The Illegals reveals the paranoia and drama of the secret lives devoted to undermining the west. A gripping history critical to understanding many of Russia's influence operations today. -- Catherine Belton, author ― Putin's People

A brilliant historical investigation that's as gripping as a Le Carré novel -- Tom Burgis, author ― Kleptopia

A splendid and most important book ... readers will leave The Illegals wide-eyed and open-mouthed at the stories of the illegal spies, but also with a new understanding of Russian political history ― Scotsman

An authoritative history of Moscow's continuing deep-cover spy programme ― Irish Times

Shaun Walker skilfully shows how Russia's modern day election meddling is rooted in the subterfuge and trickery of the bad old days. A fascinating read -- Oliver Bullough, author ― Butler to the World

A fascinating and brilliantly researched account of an opaque approach to espionage -- Eliza Manningham-Buller, former head of MI5

Sinister, clandestine and deadly - this is essential history, and it is happening now. A fascinating study of the Russian use of illegal deep undercover agents against the West -- Simon Sebag Montefiore

A riveting spy thriller, which doubles as a secret history of Russia that's too current for comfort. -- Peter Pomerantsev, author ― How to Win an Information War

A gripping, brilliantly researched history of the biggest group of deep-cover spies in intelligence history. Shaun Walker shows that Russia's secret illegals were far more successful in both Britain and the United States under Stalin than under Putin -- Christopher Andrew, author ― The Defence of the Realm: The Authorised History of MI5

This gripping account takes you into a world of shadows and mystery, the long and chequered history of the Kremlin sleeper agents. In the annals of espionage, they were Russia's great gamble. Shaun Walker has written a spying classic -- David E. Hoffman, author ― The Billion Dollar Spy

An incredibly moving history of the Soviet Union's boldest and most secretive spy program. Walker shows how a nation torn between survival and nostalgia invented a form of espionage that was both inspired and fanatical, delving into the deepest levels of espionage where even spies fear to tread -- Joe Weisberg and Joel Fields, Executive Producers ― The Americans

Groundbreaking, authoritative and exhilarating - this book is essential reading for anyone wanting to understand Russia's clandestine malign activities. Built on true life stories as good as any spy novel, it blows open the secrets of Russia's deep cover illegals spy program, beloved as much by Putin today as previous dictators in the Kremlin like Stalin -- Calder Walton, author ― Spies: The Epic Intelligence War between East and West

Praise for The Long Hangover:

The Long Hangover is considered and careful and humane, and should be compulsory reading for any politician considering engagement with either Moscow or Ukraine. It's not only the best book I've read on Putin's Russia, but also has great resonance for the age of Donald Trump and Brexit.

-- Oliver Bullough ― Observer

The author must be a great listener and a careful interviewer to win the trust and confidence of all these individuals. -- Svetlana Savranskaya ― Washington Post

Shaun Walker has not only done the hard and necessary work of reporting from Russia and Ukraine, he has also reflected, with remarkable historical and literary sensibility, on what it means when a great power gives up on its own future and decides instead to market its past. -- Timothy Snyder, Yale University

The best history of the ideologies and politics behind the headlines ... Walker's meticulous documentation of the annexation of Crimea and the subsequent occupation of Ukraine makes this exemplary political history, but The Long Hangover will be remembered, and re-read, as a history of memory. -- Linda Kinstler ― Times Literary Supplement

Some of the finest journalism of the post-Soviet era. Highly recommended. ― Library Journal, starred review