John Allen Kuchar Zegrus (ジョン・アレン・カッチャー・ジーグラス, Jon Aren Kacchā Jīgurasu) is the reported name of a man detained in 1960 in Japan for alleged document fabrication. He was dubbed the "Mystery Man" (ミステリー・マン, Misuterī Man) by Japanese news at the time, and became a prototype for some urban legends.