Little is known about Rita DeMara’s background. She was previously a small-time criminal with minor convictions and demonstrated considerable skill with technology, including computers. DeMara stole Hank Pym’s original Yellowjacket Suit from Avengers Mansion and adapted it for her own use. As Yellowjacket, she clashed with Pym’s ex-wife, Janet van Dyne (the Wasp), during a raid on Pym’s former laboratory in New Jersey. The Wasp easily captured the new Yellowjacket when DeMara struggled with the psychological challenges of shrinking herself using the helmet’s cybernetic size-control devices. Over time, DeMara learned to cope with her reduced size.