Continuity: In the café before "'S Wonderful", the level in Henri Baurel's sherry glass fluctuates wildly between shots. Also, Adam Cook knocks over his brandy glass and it falls under the table; then it reappears, then disappears.
Continuity: In the same scene, the aghast Adam Cook brings his coffee to his lips without removing his cigarette and dunks it, but puffs of smoke continue without pause.
Continuity: When Jerry, Henri, and Adam are performing in the café, a flower pot on top of the piano moves around between shots.
Crew or equipment visible: Shadow tracks across Henri while he is seated singing "'S Wonderful", as the camera begins to pull back.
Continuity: When Kelly meets Nina Foch in the street art market, the shadow cast by the wall jumps across the pavement from shot to shot until it is four feet wide, in the space of a moment or two in the story.
Continuity: Near the end of "S' Wonderful," the position of a green car changes between shots.
Continuity: In the "By Strauss" waltz, Gene Kelly is dancing with two ladies in the café, and his cap falls off while he is kneeling. He briefly attempts to retrieve it, then leaves it where it is.
Audio/visual unsynchronized: When Jerry and Lisa walk down the stone stairs to the river for the first time, the sound their steps make indicate the stairs are really made of wood.
Continuity: We see Oscar Levant in his studio three times. When we first see him, alone, he is playing a black baby grand. The second time, he is playing a brown baby grand upon which Gene Kelly dances. In the third Levant studio sequence he is alone, again, playing the black grand. Perhaps the brown piano was fashioned to accommodate and withstand Kelly's dancing on it.