Combine two kinds of crazy stunt and you get insane squared, which is evidently more fun than anything human beings have done EVER. These guys blend highlining—tightrope walking on four-inch-wide bouncy straps stretched between skyscrapers or mountain peaks—with BASE-jumping, which is fundamentally a razzle-dazzle variation of jumping off cliffs with a parachute. It is astonishing to watch a man cartwheel right off the edge of a granite precipice and keep spinning away into the abyss. This documentary recently took the best extreme sports award at the Barcelona Sports Film Festival, adding that to four other such from Autrans, La Rochelle, Val d'Isère, and Vancouver. Ah, the French—very cuckoo, no?