This work was inspired by a letter found in a public archive written by the Chief Constable of Manchester to the Commissioner of Scotland Yard in 1929. It related to a murder case (George Armstrong) in which the Manchester police found fingerprints on several artefacts, including a lightbulb, which were sent to Scotland Yard for analysis. The work comprises a photograph of the letter and a lightbulb etched with copies of the victim’s fingerprints.