Doc Magnus invented the Metal Men, a team of robots that possessed the unique strengths and weaknesses of their namesake element. The eccentric scientist also inadvertently bestowed individual personalities on the six mechanical heroes, and as a result they were sometimes too human.

The heaviest member of the group, Lead was stammering and slow-witted but always willing to take on the job at hand. As a non-conducting metal, Lead could act as a shield to protect the others from radiation and other hazards.

Lead is also highly poisonous, but no one involved with the Metal Men seemed the least bit concerned about continued exposure to the dim yet agreeable robot.