UNKNOWN (2011, UK/Germany/France/Canada/Japan/USA, 113m, 15) **½ Action, Mystery, Thriller dist. Warner Bros. (USA), Optimum Releasing (UK); pr co. Dark Castle Entertainment / Panda Productions Inc. / Canal+ / Horticus UK / Studio Babelsberg / StudioCanal / TF1 Films Production; d. Jaume Collet-Serra; w. Oliver Butcher, Stephen Cornwell (based on the novel “Out of My Head”…