“Eastern Promises” is not the movie you think it is. For a crime drama, it’s strangely bloodless. But it’s a David Cronenberg movie, so there’s a good deal of bodily harm, not to mention fluids. For a tale of immigration, or of cultural history, it’s not particularly well-shaded: few of the Russians or Chechens involved go far beyond Secret Squirrel. Yet, its history is impeccably researched, right down to the shading on the prison tattoos. Somewhere between these two frayed threads (and a truly surprising twist ending), you get a fascinating story of personal displacement – displacement from home, from the law, even from the body you walk in. There’s just not enough of it.