Professor Bullfinch has created a machine for the government which will shrink objects and be used for spying. When Danny sneaks into the lab, he and his friends discover the machine and try to use it for a problem they have been dealing with at school.
Danny knows the Professor is working on a new secret invention and is in danger, and when he and Professor accidentally switch on the new machine, problems get larger.
Are there enemy spies following professor Bullfinch? Is he working on a secret government invention? Danny and his friends Joe and Irene, decide they must warn the Professor of possible danger. They track him down in an old barn where he's hidden his workshop. Once inside all they find is a weird and fascinating machine. Danny tries out one or two levers--but he isn't prepared for what happens next! He and his friends are trapped inside the machine and shrinking fast....