Watch Hum Kaun Hai Full Movie Free Online 123Movies. Dimple Kapadia, Amitabh Bachchan and Moushumi Chatterjee star in this eerie mystery. The film centers on the Williams family -- mother Sandra and her two kids, Sarah and David, and Sandra's husband, Frank, who's away at war. Living in an isolated area with their three servants, the family begins to notice strange occurrences haunting their household. When Frank returns, Sarah tells him a horrifying secret, prompting him to investigate the mystery.