Stop me if you've heard this one before: Woody Allen made a movie about a grumpy stick-in-the-mud who fiercely barks about rationality and mortality and ends up stiffly romancing someone way younger than him. Perhaps it's hacky in and of itself to accuse Allen of withdrawing to familiar territory with his latest effort, Magic in the Moonlight, but despite the charming Roaring '20s costumes and Southern France location, the whole thing feels wearily familiar, and not in a comforting way.

Colin Firth is our caustic hero Stanley, a celebrated magician who performs in exaggerated Chinese makeup to audiences around the world, but is possessed of firm ideas about the difference between reality and fantasy. He's contracted by an old friend (Simon McBurney) to journey to the French Riviera and disprove the supposed psychic powers of a charming young woman (Emma Stone) who's hoodwinking a rich family. Will this grumpy but articulate stick-in-the-mud remain resolute before the winsome Sophie?

Firth is a charming actor when he's doing nothing, and he does his best with the material Allen gives him, which is a lot of barking in everyone's face about how they're naïve fools. Stone looks utterly lost, as she does so often in period pieces. Yes, Sophie is intended as a bit of an enigma, but Allen's plot points her in only one direction with Stanley. No kind of chemistry between the two ever arises, making their eventual romance, arrived at through pages of halting dialogue, feel particularly awkward.

It's worth noting that Woody Allen wrote Magic in the Moonlight before he was once again enveloped by past scandals, but films are watched in context and Allen's troubles are really hard to ignore while watching Firth and Stone awkwardly unite. Of course, he's been pulling this nonsense for decades now—amazing that a man who's made some of the most definitive romantic films has also subjected us to so many couples devoid of life and generations apart in age. Magic in the Moonlight is going for a screwball vibe, but screwball comedies are usually drowning in plot twists to keep things moving along. This has one, and you see it coming from a mile away.

Forget Allen's ickiness, Firth and Stone's age difference, and every performer's general half-heartedness. Magic in the Moonlight spends almost all of its dragged-out 97 minutes on Stanley and Sophie's weak cat-and-mouse game, first focused on his efforts to unmask her and then to educate her in the finer things, from Shakespeare to Nietzsche. As we drag on towards nowhere in particular, the film asks questions a baby in the audience could answer (will Sophie marry the hare-brained millionaire Brice, amusingly played by Hamish Linklater? Of course not) and then finally remembers to get to the third act far too late.

Firth's grumpy routine would have worked great for 20 minutes; stretched out to nearly 100, the eyes start rolling every time he starts bleating about mysticism serving as another opiate for the humdrum masses. The costuming and production design are lovely, and some of the supporting cast (particularly Linklater and Eileen Atkins as a wise old auntie) keep things perky when they're on-screen. One wonders if there's anything Stone could have done; her part is sorely underwritten, but we just watched Cate Blanchett (and to a lesser extent Sally Hawkins) do titanic work with thin material in Blue Jasmine last year. But that was at least a somewhat meaty drama; Magic is aiming to be frothy, but instead just comes off rather damp.