This is one of a series of caches in and around the town of Wallingford. The well known crime writer Agatha Christie owned a house in the town and spent her later years there. All the caches in this series are named after her books. The original cache (GC4KDMA) was archived several years ago.
This cache starts at the town's famous bridge and explores a little used sunken pathway - hence 'The Hollow'.
If the Castle Gardens are open they are well worth exploring - the view from the top of the Castle Mound is very good - and there's now a Virtual Cache there too!!
By answering the questions in order you should be able to find the cache which is located at
N 51 36. (A/2) A (B-F) W 001 07.(B-1) C (D-E)
After the final question continue along the path then cross the road carefully to find the cache