John Martin is a forty-something American school teacher During a vacation in Florida he takes a sip of water from a magical fountain & is turned into a twelve year-old The transformation is not permanent though & after a while John regains his original appearance Unfortunately at rather unpredictable intervals thereafter John morphs back into his child-like self being forced to lead a double life Only his wife & son know his secret & together they decide to make up a story to explain the presence of the mysterious 'little John' who they plan to pass off as a distant nephew But not everyone is so keen to believe this version of the truth This collection features all the episodes from this popular sit-com