While Dean Martin & Sharon Tate are flying in the helicopter, they swap seats at one point.
Although the two cars hit side to side several times on the mountain road, there is no visible damage to either car.
After another car tries to run Matt helm's Lincoln off a mountain road and denting in his driver side door, the door is miraculously fixed with no dent as Matt continues to drive it and gets a way.
A billion dollars in gold is exponentially more than would fit on a single train car which has a max weight of less than a couple hundred tons.
After the car is damaged at the creek Matt and Freya take two duffel bags out of the trunk and put together the helicopter. There is no way two duffel bags can hold all the parts to make the helicopter. Also, even if the engine was in one of the duffel bags it would have been too heavy for Matt to have taken it out of the trunk using just muscle power.
The villain Wen Yu-Rang and her gang appear to be Chinese however the wise cracks include references to the yen and a kimono.
In the final fight scene on the train, a trap door opens up on the floor of the locomotive and we see the ground beneath rush by. However, no railroad ties are visible. The "ground" is very likely just a treadmill belt.
After Matt and Freya are in bed and accidentally trip the emergency brake on the train, they are thrown out of bed towards the camera. The wires suspending them are visible.
It is clear that in many close-up shots, there is no windshield in Matt's Lincoln.
In the fight between You-Rang and Freya, none of the blows or kicks actually connect. Each fighter can be seen to grab at a body part that has been struck, when the blow was seen to be aimed at a different part.
While Dean Martin & Sharon Tate are flying in the helicopter chasing a train, the shadow of a very different helicopter is visible in the background.
Nixon didn't assume office until January of 69. Film was released in Canada in December of 68.
After throwing one of his 'grenades', Matt Helm leaps over a hedge and lands on a lawn which is a stunt mat that ripples as he moves on it.
The people in the helicopter when it lands at Contini's estate are obvious doubles for Dean Martin and Sharon Tate.
There are no mountains in Denmark