Th are even great historical starting points for such fiction, like the bunch of German U-Boats spread across the world (mostly the Atlantic), including one (U-234) en route to Japan with special cargo including uranium oxide, high-ranking Germans and Japanese and an Me-262.

Better starting hook that the Last Resort series (US nuclear submarine with intercontinental ballistic missiles refuses weird orders, is fired upon by the US Navy, and decides to occupy a fictitious island).