In a small British town, there is an old lady who is making the best of her weak condition. However, the small time criminal mastermind, Scunner Campbell, has stolen a new invention that he hopes will grant superpowers to himself; as soon as he makes it work that is. However, a botched firing makes the beam go astray and it hits the Grannie instead. Suddenly, the lady gains super strength and speed to become the local superhero, Supergran. Now, Supergran protects her town from the forces of evil, although Scunner Campbell is not exactly a major challenge.