Raschid Karnak was an Egyptian guide.
He was hired by Seth Rakoff to help him find a tomb described in the grimoire of Anubis. Kephri, who had been trapped in the tomb, entered Karnak without anyone realising and fed on him for months. He wore an ankh, which limited Kephri's power.
Back in Hollywood, Rakoff cast him as the Mummy in his film The Curse of the Scarab in 1938. He began to tell the Fifth Doctor and Peri of Rakoff's plans to raise Kephri, but Rakoff killed him before he could go into detail. However, the ankh was later removed, and Kephri transformed Karnak's corpse into a giant insect. (COMIC: The Curse of the Scarab)