Mysterious Island (1961)

To date, at least ten filmed versions exist of Jules Verne's 1874 sequel to his famous Twenty Thousand Leagues Under the Sea (1870) novel; this one is from Columbia Pictures, and like the others is only partially faithful to its source.
Set during the 1865 American Civil War, a small group of Union soldiers escape a Confederate prison via a hot air balloon that's conveniently moored near their cell. Once in the air their luck runs out and fierce winds blow them miles out to sea, crashing them upon the titular mysterious island, a place where strange creatures roam (when they aren't waiting quietly until needed).
The last third of the film is the most interesting provided you're familiar with the aforementioned Twenty Thousand Leagues story, otherwise you'll have to take even more on faith than the rest of us do.

3 lead shoes out of 5