Bill Foster was born in Watts, Los Angeles, California. Later a biochemist, Dr. Foster worked in the Plans and Research Division for Tony Stark's Baltimore factory. He is hired to be the biochemical laboratory assistant of Dr. Henry "Hank" Pym. At a time when the original Giant-Man was stuck at the height of 10 feet (3.0 m), Dr. Foster helps at Stark's behest find a cure to change Pym's size back to normal. Foster continues to work as Pym's lab assistant. Foster later investigates the apparent deaths of Pym and Janet van Dyne.