In the early nineteenth century over forty operas by foreign composers, including Mozart, Rossini, Weber and Bellini, were adapted for London playhouses, often appearing in drastically altered form. Such changes have been denigrated as 'mutilations'. The operas were translated into English, fitted with spoken dialogue, divested of much of their music, augmented with interpolations and frequently set to altered libretti. By the end of the period, the radical changes of earlier adaptations gave way to more faithful versions. In the first comprehensive study of these adaptations, Christina Fuhrmann shows how integral they are to our understanding of early nineteenth-century opera and the transformation of London's theatrical and musical life. This book reveals how these operas accelerated repertoire shifts in the London theatrical world, fostered significant changes in musical taste, revealed the ambiguities and inadequacies of copyright law and sparked intense debate about fidelity to the original work.