He rented a small flat at 43 Belsize Avenue, while his wife Eva was nearby at 24 Lyndhurst Road. Belsize Park was becoming the favoured destination for Austrian Jews and other refugees from Nazism, but this exiles' London was only part of English life for Brandt; his English uncles Augustus and Henry took Bill under their wing. They had large houses in South Kensington, and neighbouring country estates: Uncle Augustus at Castle Hill, Bletchingley, and Henry at Capenor, Nutley.

To their uncles, Brandt and Eva must have seemed a rackety young couple. They were married, at least, but not living together, and they were without visible means of support. On the other hand, they knew exactly how to behave in society, and Eva was both elegant and vaguely aristocratic. They were accepted as part of the family and, what is more surprising, allowed to photograph freely within their uncles' households. Brandt did not set up a studio like the one he had left behind in Vienna. For the rest of his career, his photography would be done in the streets of London, the English countryside and the houses to which he had access. All he needed was a makeshift darkroom at his flat, where he did almost all his developing and printing. Within a very short time, Brandt formed the basic idea of his first collection, The English At Home. The layout of the book would be a series of contrasts between wealth and poverty. On the left-hand pages, he would have scenes from the life of his upper-class relatives. For the right, he would find English equivalents of the outcasts he had photographed on the continent: beggars, Gypsies and drunks. By showing English life in such stark opposition, he could leave himself out of the picture: living on their £7 a week on the edge of Hampstead, he and Eva belonged to an undefined middle. Brandt did not include in his book any recognisable pictures of his relatives and their friends, nor did he show upper-class subjects "at home". Brandt wanted to show typical English behaviour, but also to bring out some quality of strangeness in even the most conventional and privileged social occasions. Brandt's photograph Kensington Children's Party was printed opposite a scene of children playing in a dismal East End street. It is also a picture of internal contrast. The balloons at the top of the frame are supposed to represent hilarity but, hanging up there with their dangling ribbons, they become frozen, uncanny objects. At the bottom of the frame, the children's faces are frozen, too, into expressions of solemn self-control.