John Travolta had worked hard on the "You Should Be Dancing" sequence and threatened to quit the film when the studio suggested it should be shot in close-up instead of full-body.

Production had to be briefly halted so that John Travolta could attend the funeral of his girlfriend Diana Hyland. The couple had earlier appeared in The Boy in the Plastic Bubble (1976), their only joint venture. It was Hyland who encouraged Travolta to take the role of Tony Manero.

Allan Carr designed the ad campaign for the film. It was so successful that producer Robert Stigwood asked him to help him produce his next film, Grease (1978).

John Travolta ran two miles a day and danced for three hours daily to get in shape for this film. In the end, he dropped 20 pounds.

There was some early grumbling about Karen Lynn Gorney when filming began. Certain crew members felt she was too old for the part, and that her dancing wasn't up to par (she had sustained serious injuries in a motorcycle accident a few years earlier).

Continuity

In the opening sequence, Tony walks down the street and it's visibly sunny and the pavement is dry. Then when he runs across the street toward the paint store, the street and sidewalk are wet from rain.

On the first disco night, there is a shot of a bar and a dancing lady, a bartender, three men sitting at the bar. Another man at the bar wearing a tan suit is reflected in the mirror behind the dancing lady. These same people are shown in the same place on the second disco night. On both nights, the song "If I Can't Have You" is played.

After Tony walks outside with Joey and his girlfriend to the car Double J is using with a lady friend, Tony walks back into the disco leaving Joey and his girlfriend far behind him. In the next shot Tony walks back into the disco for the line dance; Joey is dancing with Annette in the background of the same shot, and they all come together to dance.

At the final bridge scene when Bobby C. is climbing up the cables of the bridge, he wears white sneakers. Moments later when he's talking to Tony on the bridge's beam, he does a headstand and he's wearing black shoes.

Upon entering the discotheque in the beginning of the movie, Tony greets the same man (in blue shirt) twice.



Factual errors

When Stephanie and Tony are dancing at the dance studio the first night they get together to practice, there are Valentine's Day decorations and advertisements on the wall. When the scene cuts to later in the evening when Tony and Stephanie are walking home, the storefronts have decorations and sales flyers for Easter week.

The song "Stayin' Alive" by The Bee Gees is misidentified as "Staying Alive" in the opening-credits sequence.



Revealing mistakes

When Bobby hangs from the vertical suspenders on the Verrazano-Narrows Bridge, they wiggle quite visibly, indicating that they are made of some type of rope, as opposed to the steel found in the cables of most suspension bridges.

When Double J crashes Bobby's car through the Barracudas' hangout, obvious dummies sit in the car as the impact shot is slowed down.



Audio/visual unsynchronized

When Tony and Stephanie dance to Tavares' version of "More Than a Woman", Tony places the needle on the record, and the arm skips all the way to the end, revealing that the record player is broken and the music was dubbed in later.

When Bobby C. asks former priest Frank about getting a papal dispensation for an abortion, the camera angle changes so that the side of Bobby's face is shown and all of Frank's can be seen. Frank answers Bobby, who then says, "Well, maybe you can, maybe you could do it for me." At this point, Bobby's mouth is clearly not moving except once, which indicates that his retort was dubbed in over a one-word retort.

In the first scene that the guys pick up Tony in front of the candy store to head to the disco, it's clearly visible that the driver of the '64 Impala is a stuntman instead of Bobby C., whose voice is dubbed in and then appears as the driver in the interior car shots.



Crew or equipment visible

When Tony is first picked up in the Impala, as the boys review their inventory of pills and alcohol, the camera rigging can be easily seen reflected in the passenger window where Tony sits, especially as a lighted "TRAVEL" sign passes by.

Reflected in the mirror in the studio as Tony and Stephanie are practicing their "More Than a Woman" routine.

When Tony is walking with Bobby C. by the paint store, a crowd of people watching the scene being filmed is reflected in the last window they pass before they reach the corner.

Camera shadows in some scenes, such as on the group's car.



Errors in geography

Just before Tony gets off the subway train the first time, "45th Street" station signs are visible from inside the car. After he gets off the train, he is waiting for a train at "53rd Street". Neither station is a transfer point in the NY subway.



Boom mic visible

When Tony interrupts a dance class to ask the instructor about Stephanie, the boom mic is visibly reflected in the mirror towards the right.

As Father Frank Jr. is leaving the Manero house, when he, Tony, and the driver load the bags into the car, a boom mic shadow is visible on the top portion of the car.

As Tony and Frank Jr. approach the car door when Frank Jr. is leaving the family home, the shadow of the boom mic is visible on the tree trunk.

When Tony talks with Stephanie in her apartment after the "lonesome subway ride" scene.



Character error

When Tony is walking with Stephanie to get coffee, a girl's scream is heard. A group of girls was watching them film the scene and they would scream when they saw John Travolta.

The sign on the roof of the 2001 Odyssey disco misspells the word "Odyssey" as "Oddyssey," although the vertical sign attached to the building wall spells the word correctly.

Tony tells Stephanie about how a worker died during the making of the Verrazano Bridge by falling into the concrete. While that's a popular myth, it never actually happened.