Lord of The Rings: Fellowship of The Ring - Legolas' Arrow
The slip-up takes place in Balin's tomb.
When the Cave Troll comes in, Legolas soon gets to the trolls head. he quickly fires the arrow into the Cave Troll and jumps off. (the arrow stays in the troll's head) When the camera moves back to view the area a little better, the arrow is NOT there!!! Then, in the next few seconds, the arrow seems to reappear!
He shot it in the head and the arrow shatters. if you look on the top of the screen after he shoots it and on the left side you can see pieces of the arrow.