“Prisoners” is the most maddening kind of failure: an abrasively portentous thriller that, in spite of its copious flaws, manages to startle the audience a handful of times. Because director Denis Villeneuve regards screenwriter Aaron Guzikowski’s cut-and-dry kidnapping story as an ultra-serious treatise on torture, and because the superb cast (Hugh Jackman, Jake Gyllenhaal, Paul Dano, Terrence Howard, Maria