Alone is a horror drama. The movie revolves around Sanjana (Bipasha Basu) and her husband, Kabir (Karan Singh Grover). Sanjana’s life ruins when she is haunted by her dead conjoined twin Anjana (Bipasha Basu), who died years ago during the surgery. Anjana always hated that Kabir liked Sanjana more than her and she was always jealous of her sister. However, as the movie progresses, the truth about Anjana’s death is revealed that leaves everyone shocked.