Kalidas first appeared on screen in the drama Googleyes. She went on to play Usha in a short film called Jump Boy in 1998, directed by Menhaj Huda and written by Harsha Patel. After a number of parts in films and on television, including East is East, Bollywood Queen, My Family and Casualty, in 2002 she appeared as Monica in Gurinder Chadha's film Bend It Like Beckham. She then played the female lead Priya in the Andrew Lloyd Webber-produced show Bombay Dreams, written by A.R. Rahman, Meera Syal and Don Black. She also appeared in the BBC Television series Bodies as Dr. Maya Dutta.

Kalidas appeared in Hotel Babylon as Aisha Chaudhri, the daughter of a rich Indian hotel owner. She also appeared in the music video "Love Is Blind" by Ramzi featuring Ash King. In December 2009, she played the part of Leanne in ITV comedy drama Mister Eleven. She starred in the 2010 Chris Morris feature film Four Lions playing Sofia, the wife of protagonist Omar (played by Riz Ahmed). The film was released on 7 May.

Kalidas stated in an interview with Digital Spy that her album will consist of a variety of genres. She also confirmed that the album would include collaborations with Bashy, Skepta, Schorcer, Ramzi and Mumzy Stranger. Kalidas' collaboration with Skepta, "Cross My Heart", was released in October 2010 as the lead single from Skepta's second studio album, Doin' It Again, however, at the time of release, Kalidas firmly stated its inclusion on her debut album.

In 2011, it was announced that due to poor sales of "Shimmy", Kalidas would no longer be releasing an album with Universal Records. In the same month Kalidas was awarded the Best Female Act award at the UK Asian Music Awards, where she performed a new song, "I Like You", alongside "Shimmy" and her collaboration with Skepta, "Cross My Heart". In July 2011, Kalidas signed a new record deal with All Around The World. In September 2011, Kalidas' second single, "It's A Problem", premiered on YouTube. The single features vocals from Rapper Scorcher, who had previously been rumoured to appear on the album. The music video for "It's A Problem" premiered on 3 October 2011. The digital package of the single was released on 10 October, containing "I Like You", as well as a further new song, "Dirty Kissin'". Kalidas announced the album's third single, "A Woman Scorn" during an interview on Lorraine in November 2011. However it was never released. In June 2012, Kalidas eventually released her third single titled; "Love Between Us" which featured British Producer, DaVinChe, on backing vocals. Her debut album is due for release in 2013.

In March 2014, Kalidas released the single Don't Give Up and is currently in the studio for the release of her upcoming debut studio album in 2015. In April 2014 she released a new single called Can't Live Without You. Both singles will appear on the album. She has also covered a variety of tracks including Beyoncé's track Blue.

In June 2015, Kalidas will begin playing the role of Pinky, in the new West End musical Bend It Like Beckham. She previously played the role of Monica in the film version.