Success (1999-2005)

In 1999 Rai starred in Sanjay Leela Bhansali's Hum Dil De Chuke Sanam opposite Salman Khan and Ajay Devgan. The film was centered around Rai's character, Nandini, who is forced to marry Devgan's character despite being in love with another man (Khan), and as her husband tries to get her to her previous love, she eventually falls for him. Rai's portrayal won her critical acclaim, and the film became her first box office success in Bollywood. She won her first Filmfare Best Actress Award for the film. In the same year she appeared in Subhash Ghai's Taal, in which she played the role of a young village girl Mansi, who becomes a big Pop star after being hurt by her lover played by Akshay Khanna, the film was an average performer in India but was a big success among the international audience, especially in the United States, where it became the first Indian film to reach the top 20 on Variety's box office list.Rai received another Best Actress nomination at the Filmfare for her performance.
In 2000, she appeared in Mansoor Khan's Josh alongside Shahrukh Khan and Chandrachur Singh, in which she played a Catholic girl named Shirley who falls in love with the sibling of her Brother's enemy. The film was a commercial success. Later that year she appeared in Satish Kaushik's Hamara Dil Aapke Paas Hai opposite Anil Kapoor. It was a moderate success and her performance earned her a Filmfare Best Actress Award nomination. Later that year she played a supporting role in the Aditya Chopra's Mohabbatein alongside Amitabh Bachchan and Shahrukh Khan, the film was a major commercial success and became the second highest grosser of the year, it also earned her a Filmfare Best Supporting Actress Award nomination. Later that year, she also starred in the Tamil film Kandukondain Kandukondain, alongside Mammooty, Ajith Kumar and Tabu.
In 2002, Rai appeared alongside Shahrukh Khan and Madhuri Dixit in Sanjay Leela Bhansali's Devdas, an adaptation of Sharat Chandra Chattopadhyay famous novel by the same name. She played the role of Paro (Parvati), the love interest of the protagonist played by Khan. The film received a special screening at the Cannes Film Festival. and became the highest grossing film of the year both in India and overseas. Devdas won numerous awards including 10 Filmfare Awards, and Rai received her second Filmfare Best Actress Award for her performance. In 2003, she acted in Rituparno Ghosh's Bengali film, Chokher Bali, an adaptation of one of Rabindranath Tagore's novels by the same name. She portrayed the character of a young woman called Binodini, who is left to her own devices when her sickly husband dies soon after they are married. That year she also appeared in her home production Dil Ka Rishta alongside Arjun Rampal and Rohan Sippy's Kuch Na Kaho alongside Abhishek Bachchan, none of which succeeded.
In 2004 she appeared in Gurinder Chadha's Bollywood-style English adaptation of Bride and Prejudice by Jane Austen, Bride and Prejudice alongside Martin Henderson. In the film she portrayed the role of Lalita Bakshi, the film's counterpart of Elizabeth Bennet in Austen's novel. This was followed by Rajkumar Santoshi's Khakee alongside Amitabh Bachchan, Akshay Kumar, Ajay Devgan and Jayapradha, in the film she played a negative role for the first time in her career. In the same year she appeared in in her second film with Rituparno Ghosh, Raincoat alongside Ajay Devgan. The film was highly acclaimed by the critics, whereas Rai received rave reviews for her performance.
In 2005 she appeared in Shabd a film based on a love triangle alongside Sanjay Dutt and Zayed Khan. The film was a box office flop wheraeas it received average reviews from the critics. Her next release that year was Paul Mayeda Berges's The Mistress of Spices based upon the novel The Mistress of Spices by Chitra Banerjee Divakaruni in which she starred alongside Dylan McDermott. The film received negative review by critics and was also a commercial failure. The same year she made a special appearance in Shaad Ali's Bunty Aur Babli in a hugely popular seven-minute dance sequence for the song "Kajra Re", alongside Amitabh Bachchan and Abhishek Bachchan.