The "F.P." could stand for floating platform, or for fluffy production - take your pick. Essentially, although loosely themed on an innovative construction in the Atlantic that could facilitate transcontinental air travel, it's really just a thinly veiled melodrama that pitches the test pilot Conrad Veidt ("Ellison") and Leslie Fenton ("Capt. Droste") who designed this floating airport into a battle for the affections of "Claire" (Jill Esmond) who owns much of it. Add a little potentially destructive espionage to the mix and we've got our story. Karl Hartl could have done more with the science ...