The Moving Toyshop by Edmund Crispin
When a poet, Richard Cadogan, receives an unexpected GBP50 advance from his publisher for his new poetry book, he decides to go to Oxford for a well deserved holiday. The change of scenery and peace of mind is what he needs to recover his inspiration for writing, but little he suspects that what he envisioned as a leisurely time spent on long walks and visiting friends will turn into a mystery solving adventure full of unexpected and dangerous twists. After an eventful train journey, Cadogan arrives in Oxford late at night only to realise that he has forgotten the exact address of his stay. Relying on a distant memory of the place he boarded in years ago he accidentally enters a toyshop where, to his surprise and fright, he finds the dead body of a women. Before he knows he is knocked out and spends his first night of the holidays locked in the backroom of the shop. When he finally recovers from the concussion the body is gone and the toyshop turned mysteriously into a grocery store, and Cadogan himself is accused of trespassing and stealing food. Luckily for the puzzled poet his old university friend, the professor of literature, Gervase Fen is there ready to plunge into the midst of this mystery. The Moving Toyshop, first published in 1946, is Edmund Crispin's most famous novel featuring eccentric amateur detective, Gervase Fen.