There are numerous references to the letter V throughout the film as well as the number 5; which is in fact represented in Roman numerals as the letter V.
The term of "Fingerman" was derived from the original Alan Moore's version which portrayed the entire Norsefire government as akin to the body. The High Chancellor was the "Head", the video surveillance cameras were the "Eye" and the audio surveillance teams were the "Ear", the "Nose" consisted of the police detectives and the public television propaganda reports were the "Mouth" respectively. Whereas "the Hand" was the term for the Secret Police with the individual agents as "the Fingers" or "Fingermen". The film adaptation however dropped the entire concept except for the term of "Fingerman".
The name Evey is pronounced EV, with E being the fifth letter of the alphabet, V being five in Latin and Y being the 25th letter (5 squared)
The tag line references 'The Bonfire Prayer.' It commemorates 'Guy Fawkes night', November 5th, when a Catholic plot to overthrow the British parliament was foiled. Several variations exist. One version is "Remember, remember, the fifth of November, gunpowder treason and plot. I see no reason why the gunpowder treason should ever be forgot. Guy Fawkes, Guy Fawkes, 'twas his intent to blow up the King and the Parliament. Three score barrels of powder below, Poor old England to overthrow. By God's providence he was catch'd, with a dark lantern and burning match. Holloa boys, holloa boys, make the bells ring. Holloa boys, holloa boys, God save the King! Hip hip hoorah! A penny loaf to feed the Pope. A farthing o'cheese to choke him. A pint of beer to rinse it down. A faggot of sticks to burn him. Burn him in a tub of tar. Burn him like a blazing star. Burn his body from his head. Then we'll say ol' Pope is dead. Hip hip hoorah! Hip hip hoorah!" It is still recited in full at the famous Lewes bonfire night celebrations in East Sussex.
The scenes in the abandoned London Underground station were filmed at Aldwych, a Piccadilly line station that closed in 1994. The branch still has tracks and electricity, meaning trains can still operate.
Andy Wachowski and Lana Wachowski, huge fans of the original comic series, wrote a draft of the script in the '90s before they worked on The Matrix (1999), which shares several similar themes.
When V meets Creedy, he says, "Penny for the Guy." In England, children ask for money to buy fireworks around November 5th, "Guy Fawkes Day." On that day, children make a Guy Fawkes mannequin to be burned on a bonfire in the evening, amid fireworks.
On a clock that has an hour hand and a minute hand, the time 11:05 makes a V. These two numbers, 11 and 5, where 11 is November, and 5 is the day of November, spell out: the fifth of November. "Remember, remember the 5th of November."
The masks that the soldiers wear outside The Houses of Parliament are JT X-FIRE brand paintball masks.
When Evey gets up from underneath the desk during V's pirate broadcast, a copy of "Watchmen", another Alan Moore comic, is on the desk in front of her.
Natalie Portman looked forward to shaving her head bald, saying she'd wanted to do that for a long time.
James Purefoy was originally cast as V. He left the project because he couldn't breathe behind the Guy Fawkes mask.
The cast and crew were only allowed to shoot near the British Parliament and the Clock Tower from midnight to 4:30 am, and they could only stop traffic for four minutes at a time.
The domino scene, where V tips over black and red dominoes to form a giant letter V, involved 22,000 dominoes. It took 4 professional domino assemblers 200 hours to set it up.