A bruised, would-be thriller that’s really a oil-and-water mix of piety and paranoia, “Captive” tries to combine popcorn-crunching entertainment with higher values and holier virtues. Based on the book “An Unlikely Angel” by Ashley Smith, it’s a fictional version of the real events that occurred when Smith, a single mother and struggling addict, was held hostage in her home by escaped prisoner and multiple murderer Brian Nichols in Georgia in 2005. The film version features Kate Mara (“Fantastic Four,” “House of Cards”) as Smith, a single mom in crisis. We meet her at a 12-step meeting, she’s late for.