This has to be a joke...

I'd heard about this as being off-the-wall even for Hitchcock. The plotting is absolutely ridiculous. To wit...Cummings swims away from cops while still handcuffed AFTER jumping off a bridge--Richard Kimble would be proud. Then, with fortune still looking over him...comes across a house owned by a blind man! Talk about lucky! But wait, the blind guy has some hyper sensitivity which allows him to judge a man's character simply by the way he talks. The blind man also knows Cummings has handcuffs on because...ummm, well he just does.
Later, Cummings manages to splice the handcuffs off...with the fan from a car
enginethat is still running. The same car by the way, which he drove from the passenger side--while still handcuffed and fighting off a woman. He's Macgyver!

Without getting into who got where and how (anybody who knows NYC would immediately see things as being logistically impossible) there's also the over-the-top patriotism.

At the time of filming, The US hadn't entered the war in Europe. Perhaps Hitchcock, whose native England was being bombed daily wanted to scare some Americans while still making them feel patriotic? That would account for the plot and the superpowers of Cummings. See? Even an average Joe can save the world from totalitarianism!!!

A truly bizarre film that should be put in a time capsule. After this, Hitchcock had to believe American audiences will fall for just about anything.