A sun-splashed noir that loses its appeal in the last act, “The Two Faces of January” is an adaptation of a novel by Patricia Highsmith, who explored similar ground in “The Talented Mr. Ripley.”

Viggo Mortensen and Kirsten Dunst are a wealthy American financier and his wife vacationing in Greece in 1962, where they meet a small-time scam artist (an excellent Oscar Isaac) who has them sized up for easy marks. Soon the two men find themselves partners in a much more serious crime, though.

The lavish period costumes and sets, and the slow-burning suspense, make this one a worthwhile directing debut from screenwriter Hossein Amini (“Drive,” “Snow White and the Huntsman”). But it lives or dies on its ending, and the final minutes here don’t jibe with the rest of the film’s cat-and-cat game.