20 Things You Didn't Know About Star Wars: Episode I - The Phantom Menace
13. Darth Maul Blinks Once For Every Line Of Dialogue He Has
Though it's often stated that Darth Maul only blinks once throughout his six minutes of screen time, it's actually three times: once when his double-ended lightsaber is sliced in two, once when he's fatally impaled by Obi-Wan (Ewan McGregor), and once more as he realises what's happened to him.
The main reason for this is that Ray Park suffered severe discomfort while wearing the character's coloured contact lenses, especially when blinking, and consequently felt that it also added an eeriness to Maul's visage.
Coincidentally, three is also the number of dialogue lines Maul has throughout the film: "Tatooine is sparsely populated. If the trace was correct, I will find them quickly, master", "At last, we will reveal ourselves to the Jedi. At last we will have revenge" and "Yes, my master."