A scientist that works for the Red Ribbon Army. He created Android 16 for the sole purpose of destroying Goku, Android 17 and Android 18 for making Cell perfect, and Android 20 (himself) to make himself immortal. He also creates android 19 to serve him, as he is easier to control than the others. He also created Hell Fighter 17, and subsequently Super Android 17. He is ultimately killed by his creations after threatening to use the emergency suspension controller on 17 and 18. His ultimate achievement is Cell, and it was implied that his original reason for being created was to destroy the entire universe, which he could have done if things had not played out the way the did in the series. He could simply blow himself up every time someone stronger than him appears.
While in his android form, he refers to himself in the third person as to conceal his true identity. Is name is pronounced "Doctor Jero".
Dr. Gero: I cleared the area of innocents, in accordance with your wishes. Do you disagree with my methods?