Dark Harbor opens with a scene almost identical to the beginning of Roman Polanski's classic early-'60s debut Knife In The Water, as a wealthy, stagnantly married couple (Alan Rickman and Polly Walker) drives unhappily toward a harbor until stumbling upon mysterious young drifter Norman Reedus. The scene is either an audacious homage or a blatant theft, particularly since the rest of the film hits many of the same notes, albeit in nowhere near as accomplished (or graceful) a fashion. At first, the couple is understandably intent on having as little to do with Reedus as possible, a process frustrated at every turn by the dark-humored whims of fate (or at least the dictates of plot), which seem intent on having Reedus stick around for as long as possible. Rickman and Walker end up housing Reedus for several days, and it isn't long until Rickman is off on a golf outing and Reedus dolled up in Marilyn Monroe drag serenading Walker with a not-very-sultry rendition of "Happy Birthday." Like Polanski's film, Dark Harbor is full of awkward silences and bitter class conflict that pits the joyless comfort and privilege of Walker and Rickman against the ostensibly free but uncertain world of Reedus' nearly illiterate drifter. Dark Harbor keeps threatening to become an overheated potboiler a la Dead Calm (another film that owes a great deal to Knife In The Water), but it never does. Which is either good or bad, depending on whether you'd prefer a campy thriller to a watchable if underwhelming and derivative drama. If nothing else, the strong performances of the three leads (particularly the understated Rickman, a terrific character actor who's seldom cast in a leading role) make Dark Harbor consistently interesting, at least until an unnecessarily nihilistic twist that would be a lot more impressive if it didn't negate everything that came before it.