The first series is a set of 25 stories about a male businessman arriving at the hotel after taking a train home from work. He encounters the mysterious owner of the hotel, an old mouse known as Gregory, who suggests that he stay a while. Soon, the man becomes drawn into a bizarre series of events taking place within Gregory House as he tries desperately to escape from this bizarre purgatory.

The second series, The Second Guest is similarly set with 25 stories, except this time the main victim is a woman who has just taken a taxi home from her best friend's wedding ceremony.