The second in the Time Interventions Trilogy. This, book, Mare Nostrum, expands on the concepts of increasing longevity, medical and scientific advances and possible future developments as revealed in the first book - all seen through the eyes of the chief protagonist, ex-Detective Inspector Charles Seymour. The continuing story traces the events which led up to the mysterious murder of one of the "Twelve," a crime systematically unravelled by Seymour, who has reluctantly taken on the task of investigating the killing.