Starring Tilda Swinton. In English and Italian, with English subtitles. Rated 14A.

Referring to a famously ejaculatory David Hockney painting, A Bigger Splash also describes the escalating pas de deux between rivals for the attention of aging rock star Marianne Lane, played with almost silent grace by Tilda Swinton. Recovering from throat surgery on the Sicilian island of Pantelleria, she’s comforted by elegant clothing design from Dior and the sexual ministrations of current lover Paul, played rather too remotely by Belgian studmuffin Matthias Schoenaerts.

Their sunny idyll is interrupted by the unannounced arrival of Harry, her former producer and partner. Ralph Fiennes here brings the kind of extroverted verve we’ve rarely seen from the English Patient star, and his energy immediately lifts the movie—although not quite enough to carry it for just over two hours. Another surprise is a young sprite called Penelope, who may or may not be Harry’s daughter. This is Dakota Johnson, who’s making a career out of characters seemingly more substantial than the movies they’re in. But this time, the part is so underwritten it doesn’t matter much.

Splash is the English-language debut of Italian director Luca Guadagnino, who already starred Swinton in his murkily enjoyable I Am Love. The new film is based on The Swimming Pool, from 1969, a French tale that had Romy Schneider toggling between Alain Delon and Maurice Ronet, with Jane Birkin as the tagalong pixie. The story is updated with references to the Mediterranean refugee crisis, although these are tied to an ending that is almost insultingly farcical in tone.

The movie’s flashbacks, jump cuts, and shock zooms add almost nothing to the uneven script, but they do underline the truly exquisite cinematography of Yorick Le Saux, who also shot Swinton in Only Lovers Left Alive. So now that you’ve been prepped, go ahead and dive in. Just don’t pretend there’s actual water in the pool.