Penny Lent, is one of the film's minor antagonists, is Gwen Grayson's best friend, does not accept the fact of having to collaborate, with the so-called "sidekicks". Penny's only power is the duplication of herself. Penny is also a naturally athletic.
Gwen is Penny's ex best friend, who is infact the dangerous criminal : Royal Pain, unlike the others, Penny knew the true identity of Gwen. She will face Will and her friends, in the final battle.
Will, is Penny's natural enemy, as she can not stand all the "sidekicks".