Viennese doctor Monte Blue is madly in love with his wife Florence Vidor--so much so that many suspect that they aren't married at all! Vidor's best friend Marie Prevost is an incurable coquette; Marie's divorce-bound husband Adolphe Menjou hires detective Harry Myers to keep tabs on his wife. Inevitably, Prevost meets and flirts with the true-blue Blue. Meanwhile, Blue's lecherous partner Creighton Hale sets his sights on innocent Vidor. Thanks to the misunderstandings of detective Myers, both Blue and Vidor are suspected of infidelity, but all ends well as doctor and wife are reunited and Prevost ends up with her male counterpart Hale. The first of Ernst Lubitsch's sophisticated sex farces, The Marriage Circle was reportedly Lubitsch's favorite film; he would remake it (and improve upon it tenfold) in 1932 as the sprightly musical One Hour With You, with Maurice Chevalier and Jeanette MacDonald. Both original and remake were based on Only a Dream, a play by Lothar Schmidt.