Dr. Gero (????·?? Dokuta Gero, lit. Doctor Gero), also known as Android 20 (????????????20??? Jinzoningen Niju-Go, lit. Artificial Human No. 20), is a genius scientist who is the mastermind behind the Red Ribbon Androids, chief amongst them the bio-organic Cell.Dr. Gero is the main antagonist of the Androids Saga and supporting antagonist in the Super 17 Saga.