(at around 10 mins) When Cpt Porthill exits the taxi and approaches his door, the lock and handle are on the right-hand side and there is no large knocker. In the internal shot of him entering, the lock/handle is now on the left side and there is a large knocker attached at about head height.
When the two cars and motorcycle move off from the lights to join the van, a long line of oncoming traffic can be seen on the other side. In the next shot, cars passing the van, there is no traffic on the other side of the road.
When the convoy is seen passing the bollard lined pavement (opp St. Paul's) there is no following traffic, but in the next shot, a little further on, vehicles can be seen immediately behind them.
When Col. Hyde is preparing the letter to be sent to Major Race, he puts the half banknotes and his typewritten note into the envelope. The half banknotes are attached together with a paper clip on the side, but the note is separate. But when Major Race opens the envelope, the banknotes and the typewritten note are all held together with the paper clip on the top.
In the close-up of the removal van at the traffic lights the wing mirror is horizontal, but in the next shot, lights turning to green, the mirror is vertical, while in the next shot, van turning corner, the passenger, Rupert, has disappeared.
The team enter the army armoury and remove a quantity of weapons and ammunition, but these are seen in the same building. Also, the sub machine guns have magazines fitted. The British military would never store weapons and ammunition in the same building and certainly not firearms with magazines fitted, for just the reasons of security. Armouries are usually manned full time anyway.
The staff car used during the arms robbery at the army camp has British Military Number plates and stick on insignia. When the raid is over and the military insignia are peeled off the car, civilian plates are shown being thrown into the boot and the car drives off still fitted with military number plates.
During the weapons robbery at the army camp, Porthill, played by Bryan Forbes, is wearing a uniform with an RASC (Royal Army Service Corps) shoulder flash, but he is missing the striped lanyard which he should have been wearing over his left shoulder. Such a lanyard, usually attached to a clasp knife stored in the left breast pocket of the battledress jacket, was standard equipment for members of the RASC in 1960.
The police would never have given the name of the boy to Colonel Hyde.
During the raid on the base to obtain weapons, the Senior Non Commissioned Officers (NCOs) on the base are wearing their red sashes incorrectly: from the left shoulder to the right hip when they should be from the right shoulder to the left hip.
When Elizabeth, played by Nanette Newman, is soaking,
apparently naked, in a bubble bath and taunting her husband, the white strapless bra or swimsuit she is wearing can be seen when she moves her left arm.
When Hyde walks out at the end, a kneeling soldier raises his rifle, but as the camera pans behind him, it is clear that he is aiming at a fixed point far to the right of Hyde and not tracking his movement to the left.
In the first scene where Friend Stevens (Kieron Moore's character) appears, he's training some people in the gym. When a young man hits the small punching bag, the wall behind him and even the ceiling shake visibly, revealing them to be obvious props.
As Col. Hyde is showing the movie of the exterior of the bank that they will rob he tells his cohorts, "This is the view of the bank that you will see three weeks from today, gentlemen." Sure enough, during the events just before the actual robbery: As the guard opens the rear door of the armored truck, the same-dressed man with a newspaper in his overcoat pocket walks past and, as the guards put the boxes on the flatbed truck, the same two women in light overcoats walk past.
The soldiers on the base and those assisting the police are seen using No 4 Enfield bolt action rifles. Given this is set in contemporary times, the soldiers should have been armed with FN FALs (L1) - magazine fed, semi auto rifles.
(around 1:04:13) After Rupert leaves the army compound, he pulls and closes the gate behind him. As he gets into the car, the face of a crew member is clearly reflected on the car window for a second, almost in close-up.
When the various characters gather for the first meeting, the shadow of the camera can be seen briefly on someone's back, as he has a drink.
At the close of Hyde's final briefing, on the night before the bank raid, the camera's shadow falls on Jack Hawkins as it dollies toward him.
Shadow of camera falls on Jack Hawkin's back just before he sits down to the dinner table in the Cafe Royal.
Shadows of camera and camera crew are clearly visible in the foreground caught by the bright sunlight just before Roger Livesey, imitating the senior officer, dismisses the review parade at the barracks.
When the convoy drives eastbound along Fleet Street on the way to the robbery they are shown passing the offices of the Daily Express before those of the Daily Telegraph. It should be the other way round: they would have passed the Telegraph before they passed the Express.