Ex-con Scott Lang (Paul Rudd) is recruited by Dr. Hank Pym (Michael Douglas) to don a suit that grants the ability to shrink in size while increasing strength. Teaming up with Pym's daughter, Hope van Dyne (Evangeline Lilly), Lang embraces his inner hero to prevent the villainous Darren Cross (Corey Stoll), also known as Yellowjacket, from weaponizing the same technology.