Anjaan Hai Koi (1969)

Anjaan Hai Koi ('someone is unknown') is a 1969 Hindi suspense thriller directed by Babubhai Mistry, the special-effects pioneer best known for mythological and fantasy films. Here he turns to a mystery, with Feroz Khan, then a busy leading man of thrillers and action films, in the lead, alongside Nalini and the dancer Helen. The story is built around a masked or unseen figure, a series of strange events and a hidden identity revealed at the end, in the style of the whodunits popular in Hindi cinema in the late 1960s, with songs and a club number for Helen.