Lady Helena Trevallier was, to outward appearances, a social butterfly. She wandered the museums and art galleries, took long horse rides and enjoyed brisk constitutionals - weather permitting - around the many city parks. She flitted here and there, rather like an exotic butterfly and had several men trailing in her wake, in the hope that she might favour them with a dance or better still allow them to escort her to one of the many social gatherings. Unusually...