A country home where some of the 20th century's most baffling murders were planned opened its doors to the public yesterday. Only one day's glimpse was allowed by the National Trust, which is spending two years restoring Agatha Christie's grade two listed Greenway House, overlooking the river Dart in Devon.

Rooms will be decorated in faithful 1950s style and displays will include items such as the buckets and spades used by Christie, her archaeologist husband, Sir Max Mallowan, and their family on summer holidays in the area. The £2.25m property was given to the trust seven years ago.

Christie's handwritten changes to many of her detective stories, including the Hercule Poirot and Miss Marple series, were put on show yesterday, along with first editions in the small library where she hatched some of her best-known plots.