Young Adrian Toomes' parents died during his early years. Adrian was raised by his older brother Marcus and found intelligent by his teachers at school. His brother Marcus became paraplegic after a motorcycle incident and the tables turned with Adrian looking after him.

As an adult, Adrian became an electrical engineer and inventor. Toomes, with his business partner Gregory Bestman, started Bestman and Toomes, a small electronics firm. It was during his time there that Toomes first developed an electromagnetic harness that would allow the wearer to fly. Toomes' excitement at his invention was cut short when he discovered Bestman was embezzling money from the company. When Toomes physically confronted Bestman in his office, he found that exposure to the harness increased his strength. Bestman fired Toomes for attacking him and assumed full control of the company. Toomes retired to a farm on Staten Island and continued to work on his harness. In the meantime, Bestman decided to sell B+T. Learning of this, Toomes adopted the guise of the Vulture, ransacked Bestman's office, and stole his money back. Having enjoyed the experience, Toomes decided to become a costumed criminal full time.