In the movie D - Underworld Randeep Hooda (Deshu) is a mechanic in Dubai, who has come home after his mother's death. His father, is a dry, gruff, police constable. Deshu, unwittingly becomes a witness to a murder, when Mangli bhai's goons chasing a man, burst into his chawl, and proceed to kill the man right there.
Roughened up by the police to act as witness, and threatened by the goons to not, Deshu keeps shut. Later, he joins a rival gang (Hashim bhai's), and proceeds to kill Mangli. Little by little, with his bravery and intelligence he manages to become Hashim bhai's right-hand man, much to the dismay of his two sons, Muqarram and Shabbir. The rest of the film chronicles his take-over of the gang, when Hashim bhai, bending to his son's wishes, allows an unwarranted attack on Deshu and his faithful lieutenant Raghav.
The film ends with Deshu, having crowned himself underworld king, dreaming of forming the "D" company and running it as a well-tuned machine from outside India's borders.