Halo revolves around a seven-year-old girl, Sasha (Benaf Dadachandji), who is in quest of her lost puppy. Having lost her mother in childhood, she yearns for mother’s love and always feels lonely even though, there is a doting father in Rajkumar Santoshi. During vacation, when all other kids are busy playing, she sits silently and doesn’t even eat properly. So, the gluttonous servant fabricates a story that a miracle will happen in form of a Halo. There comes a street dog and Sasha believes it to be the miracle, the God sent Halo. She adopts it and names it Halo. Now her life revolves around it. She sleeps, she drinks, she eats with it. Her father doesn’t object. One day Halo is lost. Sasha is terribly upset. The quest of her lost puppy takes her through the terrifying streets of Mumbai to the neurotic editor of a newspaper, for smuggling, a police commissioner (Mukesh Rishi) and a colorful gang of street urchins.