Cosykiller

What's in the box: A sealed case file of replica letters, photographs, maps, ciphers and small physical evidence such as dried botanicals, coins or pendants, all built around one historical murder.

Cosykiller sells boxed murder-mystery case files that you solve at home. Each box is a fictional investigation set in a real historical period and is filled with replica letters, photographs, telegrams, maps and small physical objects. The site lists three cases. The entry case, Shadows in the Gallery (Europe, 1946), costs £45 and has a listed solve time of 2 to 4 hours. The two longer cases, The Secret of Site Q and An Inheritance of Murder, cost £285 each, with listed solve times of between 6 and 12 hours. Some cases come in episodes, while others are solved from a single box. The puzzles rely on classic cipher work such as Vigenère, knock codes and one-time pads, along with layered photographs and fold-out maps. That suits players who like close reading and note-taking more than quick escape-room locks. The cases are written by Red Herring Games, which says it has been making mysteries since 2007. Boxes are hand-packed in Grimsby, with free UK shipping and tracked international post. For a subscription directory, the main caveat is that the site sells individual cases rather than a recurring plan, and the catalogue is small. The price jump from £45 to £285 is also steep, so the entry case is the sensible place to start. A new case, A Question of Dragons, is being funded on Kickstarter.