Fair Used. Half A Century After Mary Jordan Died, Tommy And Tuppence Beresfrod Stumble On A Note Hidden In The Pages Of A Novel, Written By A Schoolboy, That Mary Did Not Die Naturally. They Uncover A Sinister Trail Of Poison, Spies, And Subversion-even After All This Time, People Are Prepared To Kill To Keep Her Secrets. First Edn. 1976