K2, the second-highest mountain on Earth, and the mountain with the second-highest fatality rate, is the looming, mysterious star of the breathtaking but problematic documentary The Summit.

Director Nick Ryan and writer Mark Monroe's film attempts to get to the truth behind what happened on the infamous August 2008 climb, when 11 of 25 mountaineers died ascending, or descending, the Karakoram peak.

The Summit incorporates archival video footage from the ill-fated mountaineering mission, reconstruction scenes shot on K2 - capturing its top-of-the-world vistas in all their majesty - and talking-head interviews with survivors, friends, and family members. (And with actors playing some of them - this doc's integrity is a bit shaky.)

But because the filmmakers try to solve the mystery of the deaths (especially that of Ger McDonnell, a charismatic Irishman), key events of the climb are revisited (and reenacted) from different participants' vantages, making the film at once repetitive and puzzling. There is a lot of finger-pointing. Assertions are made, theories offered, but not much in the way of certainty.

One thing is clear, though. The people who lined up to tackle this 28,251-foot bump in the earth were a unique lot: brave, fearless, crazy, or some combination thereof. From Norway and Spain, South Korea, Serbia, Pakistan, France, Ireland, and Nepal, the climbers who worked their way along the snow and ice, gullies and slopes that summer were living their dream.

And then they died.

The Summit **1/2 (Out of four stars)

Directed by Nick Ryan. With Christine Barnes, Hoselito Bite, and Marco Confortola. Distributed by IFC Films.

Running time: 1 hour, 35 mins.

Parent's guide: R (profanity, death, adult themes)

Playing at: Ritz Five EndText