Mumbai, Oct 14 : Megastar Amitabh Bachchan, who is currently seen as the host of 'Kaun Banega Crorepati' season 15, revealed why he refers to actress Shefali Shah as 'Malkinji'. In the upcoming Monday episode, the quiz-based reality gameshow, will host versatile actress Shefali Shah and the revered social worker Hare Ram Pandey. Fondly addressed by his close aides as 'Baba', Hare Ram ji is a staunch devotee of goddess Durga and has fulfilled his goal of establishing his own non-government organisation named, Narayanseva Aashram, that helps rehabilitate young girls and works towards providing them a secure future. Actor par excellence, Shefali, who has created a niche for herself with her portrayal of diverse characters, will be instrumental in providing thoughtful insights during the gameplay and supporting Hare Ram ji. During a conversation with the guests, Amitabh Bachchan affectionately refers to Shefali as 'Malkinji.' The reason behind this endearing nickname traces back to the time when they shot for the film, 'Waqt: The Race Against Time.' Elaborating further, Bachchan spoke about how Vipul Shah, who is Shefali's husband, had approached him with the script of the movie and he immediately agreed to be a part of it. Interestingly, Shefali played Big B's wife in the movie. Reminiscing the days of shooting, Big B humorously said: 'Shefali is Vipul Shah's wife, and she was playing my on-screen wife. But it was the way she was on the sets of the film, that I learnt who is the 'Malkin' of the house!' 'She was in control and provided direction instructions wherever necessary. That is when I thought that she is 'zabardast',' added Amitabh Bachchan. The 2005 movie 'Waqt: The Race Against Time' is directed and produced by Vipul Amrutlal Shah. Based on a Gujarati play by Aatish Kapadia, the film stars an ensemble cast of Amitabh Bachchan, Akshay Kumar, Priyanka Chopra, Shefali Shah, Rajpal Yadav and Boman Irani. Meanwhile, Shefali was last seen in the movie 'Doctor G', and web-series 'Human'. 'Kaun Banega Crorepati 15' airs on Sony. /IANS