Other mistake: Just after Isabeau falls from the abbey tower and turns into Ladyhawke, a soldier emerges onto the roof of the tower and questions Phillipe. An arrow is then fired (by Navarre) into the left-side of the soldier. However, he initially grabs at his right-side. After a couple of seconds he correctly grabs at his left-side, before falling off the tower. (01:00:26)
Continuity mistake: After Philippe the Mouse escapes from the prison and has swam out the underwater grate hole, another scene shows soldiers riding through the peasants leaving the castle to search for him. In the background, two soldiers can be seen sitting by the moat, eating. One stands and grabs suddenly around his belt, obviously looking around for something. A while after this in a separate scene, Philippe the Mouse is shown surfacing in the moat behind these two soldiers and grabbing the knife from beside one of them and slicing away a cord on the soldiers belt and stealing his coin purse, then swimming away quietly and saying the line about 'I know I promised not to steal Lord, but I know, that you know, what a weak-willed person I am...' Obviously the scene with the soldier standing suddenly and discovering his missing coin purse should have come after the actual 'stealing of the purse' scene.
Trivia: In the days before ubiquitous digital technology, the majority of visual effects in film were "practical" effects using stuntmen and props on wires, springboards, flash-pots, et cetera. In "Ladyhawke" (which was decidedly on the low-end of visual effects budgets), one of the most dangerous practical effects is seen when Matthew Broderick and Rutger Hauer have a heated discussion in the woods and seem about to part company. As Broderick turns to leave, Hauer's 53" longsword sizzles past the boy's left shoulder and embeds in a tree trunk, to Broderick's horror. In fact, the steel sword was real and hurtled to its target on a guide-wire, barely 8 inches from Broderick's back. If you slow-advance the scene, you can see the sword actually changing trajectory in-flight, it was so unstable. The sword came up in a Hollywood memorabilia auction in 2002 but was not sold. http://www.icollector.com/Rutger-Hauer-prop-special-effects-sword-from-Ladyhawke_i169815.Charles Austin Miller
Phillipe: When you kneel before the altar, how do you get up again?
Imperius: You sacrilegious young imp.