Alfred Crossley was one of the most prolific collectors of natural history specimens in Madagascar during the 19th century, with several vertebrate species named for him and numerous vertebrate and invertebrate holotypes to his credit. Yet the details of his life, and even of his professional activities, have been almost completely lost to history. Here I assemble what is known of Crossley's Madagascar itineraries in the years between 1869 and 1877, with the aim of providing a basis for more precisely pinpointing his many collecting localities. With the aid of a newly rediscovered obituary and contemporary press extracts, I also outline the details of a productive and drama-filled life that began with shipwreck and captivity in Madagascar and ended in a lonely death there, possibly under dubious circumstances. I also seek to understand why Crossley attracted so little attention while doing such visible and significant work, concluding that this lack of recognition was due partly to humble social origins in an era of gentlemen scientists and partly to an exceedingly retiring personal disposition.