The new DVD The Sharp End ($25.95, senderfilms.com) drags you by your optic nerve on a tour of the vertical world’s most heart-pumping deeds: high-alpine free soloing; knots for pro on Czech sandstone; wafer-hooking aid; wing-suit madness; and a parachute-protected Eiger ascent. A solid extras menu delivers a “making-of” segment, hard big-walling footage, and a hilarious machinegun monologue from one Hank Caylor. This personality packed film also lets you hear from the envelope-pushers themselves, much more than your typical climbing porn. I can’t shake the footage of a strangely calm Alex Honnold onsighting a hard, sandy, nearly unprotected 100-foot arête in Eastern Europe, after his partners deemed it a suicide mission. The film also poses the question Why? (as in, “Why risk all for a climb?”), but the climbers don’t really have an answer. On the sharp end, it seems, such questions are dead weight.