This book invites the reader behind the scenes of the history of modernist architecture. The author presents an intimate portrait of a hitherto unknown Czech architect František (François) Sammer (1907– 1973) in the context of the great works of the internationally renowned artists, and in an innovative way ushers the reader into the world of Le Corbusier’s work. Using photos from Sammer’s collection, she reconstructs the social network that gradually emerged in the atelier. She reveals the importance and value of the friendship amongst leading actors in avant-garde architecture of the first half of the twentieth century, together with those who remained in their shadows. This community, the ‘Le Corbu- sier Galaxy’, has shown a remarkable vitality and in its own way remains active even today in the network of people who keep the legacy of this famous architect alive. The impulse to write this book was the author’s discovery of a collection of photographs assembled by Sammer, which she discovered in Pondicherry, India, in 2016. After arriving in this French enclave in 1939, Sammer soon became part of the community of the Sri Aurobindo Ashram there. In 1942 he enlisted in the British Army, leaving all his belongings with the ashram for safekeeping, including his collection of photographs. Made from 1931 to 1939, the collection reveals the social circle of the Le Corbusier and Pierre Jeanneret studio at 35 rue de Sèvres, Paris, known as the ‘atelier’. For two years Sammer was one of its closest collaborators, and after leaving Paris he was involved in large projects in the Soviet Union, Japan and India. He remained in close touch with friends from the atelier by means of correspondence and visits and he also often followed their advice about where to travel. The book is the result of more than ten years of research in the Czech Republic, France, the United States, Canada, Great Britain and India. It presents Sammer’s international career, and, through him, adds considerably to what we know about Le Corbusier. The author identifies the people, times and places in these pho- tographs chiefly with the help of primary sources and she presents them as part of the history of the international avant-garde. The book consists of three parts. The main text is preceded by the author’s ‘Research Diary’, in which she discusses how her work proceeded, the circumstances surrounding the discovery of Sammer’s col- lection, and what followed immediately afterwards. The main text is written as a narrative, with the chapters arranged chronologically. It is followed by four ‘Excursions’, each of which comprises written and photographic documents from and about Sammer’s travels. Several levels of content intertwine. The story level of the main text includes footnotes with factual details. Another level comprises a total of 380 illustrations accompanying the text. The pictures may sometimes also be understood largely on their own, with the help of short quotations and glosses from related primary and secondary sources. Sammer is an unusual figure in the history of modernist architecture. His contribution and importance cannot be properly assessed through the number of his designs that were actually built or the number of winning competition entries, nor can they be fully understood using only formal analysis of his archi- tectural works. He did not write anything about himself, and before this publication little, apart from an article by the author in 2016, 1 had been written about him. Though few of his architectural or urban plans were carried out, all the greater is his legacy in his extensive, hitherto unpublished correspondence and contemporary documents, particularly in Czech, French and English, which, for decades remained deposited, unnoticed, in various places around the world. It is in this legacy that Sammer’s extraordinary importance for the history of architecture lies. The story of František Sammer unfolds from his work with great figures and visionaries of the modernist movement between the two world wars. Le Corbusier in Paris, Nikolai Kolli, the Vesnin brothers, and Moisei Ginzburg in Moscow, and Antonín Raymond in Tokyo. All quickly recognized his technical abilities and talent, and entrusted him with work in their architectural studios and with supervising the execution of their plans. The evidence shows that Sammer was actively involved in the creation of groundbreaking works of modernist architecture in the twentieth century. In the studio of Le Corbusier and his cousin Pierre Jeanneret, Sammer participated closely in work on the Pavillon Suisse of the Cité internationale The Le Corbusier Galaxy: The Photograph Collection of František Sammer Martina Hrabová 191 1| Martina Hrabová, Between Ideal and Ideology: The Parallel Worlds of František Sammer, Umění / Art LXIV, No 2, 2016, p. 137 – 166.