An airman climbs higher than any record to find out whether creatures live in the sky. A doctor resting on a farm in Derbyshire grows worried about sheep that disappear near a cave. A special train hired in Liverpool vanishes in broad daylight between two stations.
These twelve stories, six of terror and six of mystery, are by Arthur Conan Doyle, the creator of Sherlock Holmes. Here there is no detective: reasonable people face what they cannot explain.
Short and tense, each one can be read in one sitting in the language you are learning.
