The Mystery of the Purple Bentley Josephine Elder
Late one evening, Dr. Letitia Maxwell, summoned to the hospital to attend an urgent case, steps into a purple Bentley - and disappears. Helen Ross, her nurse-secretary, leads the search, negotiating a disappearing corpse, a yellow aeroplane, an emergency operation in a remote Highland castle, and solving many problems by her medical knowledge. Originally publsihed in 1932.