Sarojini-Saz-Campbell comes to India to search for her biological mother. Adopted and taken to England at an early age, she has a degree from Cambridge and a mathematician's brain adept in solving puzzles. Handicapped by a missing shoebox that held her birth papers and the death of her English mother, she has few leads to carry out her mission and scant knowledge of Calcutta, her birthplace.

Luckily, she has Chiru Sen, an Elvis lookalike, as her guide. Together, Saz and Chiru chase the mirage of a lost mother, helped by Chiru's band members and his friend Suleiman, master bookie of the racecourse. When luck leads them to a slum, Jamuna, a housemaid with a troubled past, presents herself as the likely candidate. As Saz settles into the routine of slum life, a second candidate, Urvasi, presents herself, emerging from the very opposite end of the spectrum.

With Saz split in half, nothing is spared in the battle between the mothers, moving at a fast clip to the final throw of the dice as rivals await the result of DNA matching from their blood samples. But will the verdict of science settle the puzzle of motherhood for Sarojini? Or will it be left to the judgment of Suleiman the Wise, King of the Racecourse, the bearer of ancient wisdom, to arrive at that supreme revelation?