Revealing mistake: When Maria is cradling the dead Tony you can see Tony's chest heave as the actor takes a breath.
Continuity mistake: When the Jets are playing basketball and Bernardo catches the ball, the position of the legs of the guy in the violet shirt differ between the first and second shot.
Continuity mistake: In the bar, when the cop is asking where the fight is going to take place, he addresses a guy in the back. His position and that of his tie changes in half a second when the angle changes.
Continuity mistake: When Riff is talking with Bernardo at the bar, the first shot shows one hand bent over the table. A frame later both arms are crossed together.
Continuity mistake: In the bar, when the cop is asking where the fight is going to take place, he addresses a guy in the back. His position and that of his tie changes in half a second when the angle changes.
Continuity mistake: In the prologue, after the gangs jump over each other in the alley, Snowboy and Baby John both chase Bernardo, while A-Rab and Action go the other way to chase a different Shark. In the next shot, they are all together chasing the Shark A-Rab and Action were following.
Other mistake: During the dance at the gym, Maria doesn't snap each time she should have. Natalie Wood was unable to snap, so it was dubbed (as well as her singing, which was dubbed by Marni Nixon).
Continuity mistake: When the camera zooms into the basketball field, the shadow of the Jets points in a 8 o'clock direction. In the close ups it's a 2 o'clock.
Continuity mistake: After the Jets and the Sharks have challenged themselves, Tony takes his right hand to his tie, but the immediate shot shows the hand by his side.
Answer: Actually there were a number of changes made in the movie adaptation compared to the original stage version. There were cuts, new additions, and changes to music, lyrics, dialogue, and characters. A few of the musical numbers were switched around because it was felt the storyline flowed better on screen, for different reasons. Some examples are "Gee, Officer Krupke" and "I Feel Pretty" which are cheerful, light-hearted songs and were moved to before "The Rumble", and "Cool" was moved to after "The Rumble" which gives that song's lyrics gravitas.
Super Grover ★