Soul Mates of the Lost Generation recovers for contemporary readers one of the last great collections of letters of the Jazz Age. It is the correspondence between the pioneering novelist John Dos Passos and a young woman named Crystal Ross, to whom he was engaged and who reveals herself as one of the truly daring, vivacious spirits of that extraordinary time. Before his passing in 2015, Ross's son, the esteemed literary scholar Lewis M. Dabney, completed a dual biography of the couple's time together based on this rare correspondence.

The bulk of the letters were written between 1923 and 1928, during Dos Passos's first major creative period. The letters relate scenes from the pair's life in the rich culture of Paris in the 1920s and their association with Hemingway, the Fitzgeralds, and other figures of literary modernism. Engaged in 1924, Dos Passos and Ross often corresponded about their ongoing work and the work of others in Dos Passos's circle. Dos Passos introduced his fiancee to Hemingway, and the couple accompanied him and other writers on an early trip to Pamplona, the setting of The Sun Also Rises, in which Ross makes a cameo appearance. This collection of never-before-seen letters offers rare insights into the life of the influential modernist author of Manhattan Transfer, The 42nd Parallel, and The Big Money, and into that of a remarkably independent, fascinating woman.