Hugo Marston novels

"Hugo Marston's friend Paul Rogers dies unexpectedly in a locked room at the American Library in Paris. The police conclude that Rogers died of natural causes, but Hugo is certain mischief is afoot. As he pokes around the library, Hugo discovers that rumors are swirling around some recently donated letters from American actress Isabelle Severin. The reason: they indicate that the actress had aided the resistance in frequent trips to France towards...