Goofs

When Glenn (James Stewart) turns up late for their date, Helen (June Allyson) is asleep. When she is woken by him and hops out of bed, she has her shoes on. Later, it looks as if she goes back to the side of the bed to put on the shoes she is already wearing.

When Glenn and Helen are discussing if he should quit his band job and continue his formal music studies, Glenn begins the process of tying his necktie and is not wearing a jacket. When next seen, about 6 seconds later, his tie is done, and he has on a suit jacket.

When the band is playing Chattanooga Choo Choo, the bass player goes back and forth wearing sunglasses, then regular glasses.

When the band starts playing "In the Mood", Glenn Miller is shown wearing a Captain's insignia on his shoulders (two silver bars). Later, during "Chattanooga Choo Choo", he is wearing a Major's insignia (gold oak leaf) on his overcoat. However, when "American Patrol" is played later, he is once again wearing a Captain's insignia.

Towards the end of the movie, Helen, Si and Chummy are listening to the Glenn Miller Band's radio broadcast. Chummy MacGregor and Si Schribman are standing next to the radio in Helen's living room and Chummy is resting his hand on Si's right shoulder. In the next shot, Chummy's hand is no longer on Si's shoulder - it is hanging down between the two men.

Miller's famed swing instrumental of "Little Brown Jug" is depicted in the closing scene as a "special arrangement" Glenn created for a Christmas 1944 radio broadcast by Miller's AAF Band from Paris. In fact, it was one of the real Miller Band's first bona fide hits in 1939, arranged by the recently hired Bill Finegan, who became, along with arranger Jerry Gray, two of the key behind-the-scenes craftsmen that helped mold Miller's civilian band into the enduring commercial and artistic powerhouse it became.

The Millers are purported to have their two adopted children at the time of their 10th wedding anniversary in 1938. In fact their children were adopted in 1943 and 1944.

A V1 bomb is seen falling on London several scenes before the announcement of D-Day. In fact, the first V1s fell on London a week after D-Day.

When confronted by the Commandant of Cadets about playing jazz marches, Miller was neither sheepishly deferential nor was he "rescued" by another officer whose children were fans. According to biographer George T. Simon, when the Commandant said Sousa's marches had served the Army just fine in WWI, Miller's response was "Major, are you still flying the same planes you did in the last war?"

Frances Langford never performed with the either the civilian or AAF bands, and The Modernaires only sang with Miller's civilian group.

When Glenn and Helen arrive in their car and are hounded by fans for autographs, one of the eager fans accidentally smashes into Helen's (June Allyson) head prompting her to hold her hand up to her face while she smiles.

Whether scripted or not, this is a normal reaction from someone who feels pain from being hit but is still trying to be gracious.

A newspaper states that the Glenn Miller band will be performing at the "Glenn Island Casino". In the next scene, the electric sign correctly reads "Glen Island Casino". In reality, Glen Island is spelled with a single "n"; the newspaper story had a misprint.

Newspapers often have spelling errors; very understandable in an era without "spell check" and an article that has two different spellings for a same-sounding word.

The same passengers ride the elevated "Angel's Flight" streetcar in two separate pawn shop scenes (revealing them to be mere mannequins).

During the 'String of Pearls' scene, the moonlit sea through the window behind Helen Berger Miller appears to be completely static.

During the "In the Mood" sequence, shortly before the alarm sounds and when the camera sweeps across the listening soldiers, one of them looks straight at the camera for almost the whole length of the shot.

After Helen is hospitalized and Glenn is selling the vehicles to pay off the band, Chummy offers to drive the guys to the station. Looking at the windshield, soap running down the glass. It's not snow on the roof, it's foam. The snow seen on the road previously must have been foam as well, because it sat on top of the mud and looked soupy instead of slushy.

When Glenn is removing Langford's coat in the hanger, she says, Thank you James.

The newspaper montage leading up to the Glen Island Casino scene incorrectly identifies the location as Glenn Island, as if it were named after Glenn Miller.

When Glenn Miller conducts an army band on an airfield, a Boeing B-29 "Superfortress" bomber is seen in the background. At that moment the B-29 existed only in prototypes and was a well-guarded secret, not for such wide display.

As the troops are marching on the parade field and Capt. Miller is conducting the band, the background shows different aircraft on static display. One aircraft is a HU-16 Albatross, used for Air and Sea rescue. This aircraft type did not fly until 1949 and was first used in Korea, 5 years after the movie date line takes place.

Miller's Army Air Force band plays while Negro and Caucasian troops march by side-by-side. The US military was not integrated by unit until after WWII.

Miller's first band plays "Over the Rainbow" in 1937, two years before it was released.

The British flags (Union Flag) shown in two of the UK scenes are missing the diagonal red cross of Ireland which was added in 1801.

The best-known solo on a Miller record, Bobby Hackett's cornet solo on "String of Pearls", is presented as being played on a trumpet.

There are several instances of musicians being out of sync with the playback.

When Glenn is sitting up all night rewriting "Moonlight Serenade", the camera pulls back too far, revealing the edge of the set and a cable on the floor.

Judging by the mountain range in the background, Glenn and Helen are at the Universal City studios in the San Fernando Valley. Both of Glenn Miller's major feature films were produced at the 20th Century-Fox studios in West Los Angeles.

When conducting the military band, James Stewart marks the second beat to the right. In 4/4 marking the second beat is marked to the left. It is only marked to the right when it's 3/4.