Jeff Angelo was the grandson of Mrs. Angelo and a resident of Leadworth. He apparently lived with his grandmother, and had a fondness for viewing dubious material on the internet. The Doctor got him to send a virus to various alien experts, transmitting across the world to defeat Prisoner Zero. He was praised as a hero by the Doctor, who implied to Jeff that at least one of the alien experts would offer him a job. (DW: The Eleventh Hour)
Jeff is extremely good looking, but is perhaps not the sharpest knife in the drawer.