Lamba's long term ambition was to become a journalist. While studying for a degree in Delhi, Lamba pursued modelling as a hobby and soon became a well-placed model in the Indian modelling industry. Examples of Lamba's early modelling work include several television commercials for companies such as LG, Sony, Cadbury, Hajmola, Airtel, Sunsilk, and also others.In 2004, she majored in English with honours from the University of Delhi.Then came her first movie in 2005 called "Yahaan", which was directed by Shoojit Sircar. In 2008, she acted in Siddharth Anand's film Bachna Ae Haseeno which stars Bipasha Basu, Deepika Padukone along with Ranbir Kapoor in the lead roles. This movie is produced by Yashraj Films.
