Rudi Dharmalingam made his TV debut in 2002, in the BAFTA Award-nominated drama series Cutting It. He acted on the series until 2004. Later in 2004 he understudied the role of Dakin in the original London stage production of The History Boys at the Royal National Theatre. In 2006 he made his Broadway debut in the transfer of The History Boys, this time playing the role of Crowther. In 2005, Rudi Dharmalingam played the titular role in Tom's Midnight Garden, the opening production of the Unicorn Theatre, the UK's first custom built venue for children, the , in 2005.