Continuity mistake: One of the bad guys prepares a tea tray in the boat's galley and carries it up to the bridge. Throughout his preparations and his trip up the stairs to the upper deck, the contents of the tray keeps changing. The items rearrange themselves, and the size and shape of the bread loaf alternates several times.
Revealing mistake: In the aerial shot from the helicopter as it overflies the Village, another "real world" car can be spotted parked next to the Green Dome.
Free for All - S1-E4
Continuity mistake: The number of toast slices in the rack on the breakfast cart changes between shots. Number 2 takes a piece, leaving three. No one's gone near the cart, but a moment later, the toast rack contains five pieces.
Continuity mistake: The cape Monique is wearing disappears when she's in the watch shop, then reappears a few shots later.
Factual error: Alison's Polaroid pictures develop themselves instantly. (In reality, you had to wait just over a minute before separating the developer sheet and finished photograph.) She also leaves the same flash bulb in when she takes a second picture - and it flashes again.
Revealing mistake: Watch Curtis' shadow when he and Number 6 have their pistol range competition. The split-screen process cuts his shadow in half.
Revealing mistake: When the red handkerchief is tied to Number 6's hand, Patrick McGoohan's wedding ring is visible in the close-up.
Continuity mistake: While Number 6 is being dragged behind the horse, a red bandanna tied around his hand disappears and reappears several times between shots.
The General - S1-E6
Continuity mistake: Number 6 is quite a quick-change artist. In the projection room, after the countdown reaches 2 minutes, he manages to: strip the unconscious technician; take off his own black suit, tie, hat and glasses; get into the white lab outfit, and finally, don all the communications gear in time for the 1-minute countdown announcement.
Continuity mistake: When Number 6 is pushing him on the swing, the Butler's hands and arms change positions instantly between shots. One moment, he's holding the rope with his hands: in the next, he has his elbows crooked around the ropes instead.
Free for All - S1-E4
Continuity mistake: It's high tide when Number 6 escapes in the boat, but when he's brought back just a few minutes later, the tide is out.
Continuity mistake: Just before the fight begins on the roadway, Number 6, in full shot, steps off the grass and onto the road. But the next close-up of him shows him on the grass again.
Continuity mistake: Number 6 is taking notes on the Village inhabitants, trying to determine which of them are prisoners and which are keepers. Next to the pond, he's observing Number 62. But on his notepad, he crosses out Number 8.
Continuity mistake: The sling that's been around the Butler's arm and shoulder vanishes after he fans Number 2 with a towel. It's back a few shots later.
A. B. and C. - S1-E3
Continuity mistake: When Number 6 kicks out the grill, his socks are blue. In the next shot, though, the socks have turned brown.
Continuity mistake: When Number 6 jumps from the gunrunners' boat, he's on the starboard (right) side. In the next shot, though, the bad guy shoots at him from the boat's port (left) side. (00:20:30)
Revealing mistake: Number 6 sets up exercise equipment in the woods and performs several athletic stunts on a bar. In close-up, he's bare handed. In long shots, however, the stunt double becomes apparent because he's wearing gloves.
Continuity mistake: The windows in Number 6's flat are curved on the inside (as is the wall). But on the outside, the windows are flush against a flat wall.
Revealing mistake: While they ride toward the helicopter, Number 6 and Number 2 have a conversation. Shots of Number 6 are obviously outdoors under windy conditions: his hair is blowing. But every shot of Number 2 has been taken in-studio with a rear-screen projection. His hair isn't moving at all.
Continuity mistake: While Number 6 is in the jail cell, he lights a cigar and starts blowing smoke. Just a few shots later, the smoke has vanished and he lights the cigar again.
Answer: It's even more obvious than you think, you know who number 1 is in the very first episode. When 2 replies to the question "who is #1?" Change the way he answers from you are number one (in the monotone or accented answer to, "You are, number 6. The comma gives you the answer. #6 is #1. It's the tone of the answer.