Hey, I saw something early! Good for me!
As the barrage of trailers have now informed you, this is the story of one Col. Klaus von Stauffenberg, a German military officer who joined and subsequently spearheaded an attempt to assassinate Adolf Hitler and stage a military coup against the Nazi Elite. You are aware, one hopes, that this didn't work.
So, here's a challenge facing anyone trying to film this story: Everyone knows Hitler wasn't assassinated, so even if you've never heard this particular story you know how it ends. There's two ways, then, to make this work as a narrative (as opposed to a documentary). Option #1: Make a sprawling, likely lugubrious epic that sets up all the context and backstory explaining how things got to this point, who these conspirators were and why they chose this moment to act which won't be especially riveting but will tell a fascinating historical tale. Option #2: Cut out every shred of context, larger-themes, ANYTHING that isn't directly related to the forward-momentum of the conspiracy and hope that avoiding context will let the audience briefly forget that they already know the ending and can get wrapped up in the thrill of the chase.
"Valkyrie" goes with Option #2.
It's a well-made mechanical thriller, it just doesn't have any real heft to it. There's no real depth or character to any of the players or the film they inhabit: Tom Cruise - as Stauffenberg - steps onscreen, announces that he's decided that Hitler must be stopped, and spends the rest of the film plowing ahead toward that goal. The movie follows his lead. Who were these guys? What were their motives aside, from the general "Hitler was bad?" No time for that - it's just straight-on through the exciting parts of what's ultimately a pretty damn clever power-grab.
Up to a point this all works, the movie is exciting and goes along quick and agreeably... there just isn't anything to hang onto after it ends. Change the costumes and this could be the second and third act of an Ocean's Eleven sequel.