In the first segment of the Marvel Studios panel at Comic-Con International: San Diego, Marvel Studios' President Kevin Feige introduced previously cast actors Corey Stoll as Darren Cross/Yellowjacket and Hope Van Dyne, respectively, for 2015's Ant-Man.
Actor Michael Douglas, who will play an elder Hank Pym, described Stoll's role in the movie as a former business partner of Pym's who took control of his company and sent it down a dark path. Pym then recruits Rudd (playing Scott Lang) to service as a new Ant-Man to save his company and legacy.
Not much was said on Lilly's character of Hope Van Dyne, but was described as the daughter of Hank Pym. There is no "Hope Pym" in comics, but there is a Hope Van Dyne in an the A-Next alternate universe who is the daughter of Hank and Janet Van Dyne, so presumably this is an instance of Marvel borrowing from a side story to fit their plans for the movie. In A-Next, Hope became Red Queen, a villain who helped in the formation of an anti-Avengers team called the Revengers.