Hadji Singh is a streetwise 11-year-old Kolkata orphan who becomes the adopted son of Dr. Benton Quest, as well as Jonny's best friend and adoptive brother. Rarely depicted without his bejeweled turban and Jodhpuri, he is proficient in judo, which he learned from an American Marine. The seventh son of a seventh son, Hadji seems to possess mystical powers (including snake-charming, levitation and hypnotism), which may or may not be attributed to parlor trickery. The Quest family meets Hadji while Dr. Quest is lecturing at Calcutta University; he subsequently joined the Quest team after saving Dr. Quest's life (by using a basket lid to block a knife thrown at the doctor). Although slightly more circumspect than Jonny, he can reliably be talked into participating in most any adventure by his adoptive brother. He is voiced by Danny Bravo.