Free for All - S1-E4
Continuity mistake: Throughout the episode, Number 6's lapels switch from having solid to broken white piping and back again.
Continuity mistake: Number 6 chooses a rather thin tree to cut down and fashion into his canoe. Somehow, when he's finished hewing out the wood to form the boat, it's considerably wider than the tree he started with.
Continuity mistake: The Villager Rover attacks changes outfits several times between shots. He's wearing a striped sweater that turns into a pink jacket that turns back into the sweater, etc.
Continuity mistake: At the end, the computer produces a print-out with two lines of type at the bottom, then pauses. In the next shot, when it starts printing again, the two lines have disappeared.
Continuity mistake: During the opening sequence, a white car parked outside the prisoner's London flat disappears between shots as he drives up in the yellow Lotus and walks to the front door.
A. B. and C. - S1-E3
Revealing mistake: In the fight at the end of the B scenario, Number 6 has a small problem. His pants split open in the back. Fortunately, they somehow manage to mend themselves again.
Revealing mistake: Though the Village isn't supposed to have automobiles (only the little "golf cart" transports), there are several parked cars visible in the shot of Rover floating down to attack the fleeing Villager.
Visible crew/equipment: In the foot-chase-on-the-beach scene, there are tracks in the sand from the camera crew's truck. They vanish and then reappear when the camera angle changes.
Continuity mistake: In the beginning, the cards and notebook on Number 6's kitchen counter change positions between shots. There's also a circle card on the counter that disappears when he draws the star card from the deck.
The Girl Who Was Death - S1-E15
Audio problem: For some reason, "Londonderry Air" was dubbed over the original song being performed by the actors/singers. Their lips aren't moving in sync with the words at all.
Revealing mistake: At one point, Rover rolls past the Village retirement home, but the film in this sequence was for some reason shown in reverse. Smoke from the building's fireplace is flowing back into the chimney instead of coming out.
A. B. and C. - S1-E3
Continuity mistake: While Number 6 follows Number 14 around the Village, her briefcase keeps switching itself from her right hand to her left between shots, without her having moved it. Later, when she enters the hallway, the case disappears altogether.
Continuity mistake: On the beach, the Queen is sitting on a large rock and conversing with Number 6. Then she's seen standing down near the water. After an abrupt cut, she's back on the rock without enough time to have moved there.
Revealing mistake: When Number 6 first enters the bedroom, the light that hangs from the ceiling is moving as though someone has brushed against it. But there's no one else in the room.
Free for All - S1-E4
Continuity mistake: Number 2 has a nice, bright red handkerchief peeking out of his pocket when he leaves the house. But between shots, it turns itself into a blue handkerchief.
Continuity mistake: The maid comes back to Number 6's house for the feather duster she left behind. While they talk, the duster changes positions on the table all by itself.
Do Not Forsake Me Oh My Darling - S1-E13
Audio problem: When Number 6 tells the Kandersfeld waiter that he took some photographs, we hear his words, but his mouth doesn't move.
Revealing mistake: Number 6 is supposedly flying the helicopter, trying to escape from the Village. There are shadows from the rotor blades crossing his face as he pilots the aircraft. But look closely at the top of the transparent cockpit bubble over his head: you can see the real copter blades - completely stationary and not moving at all.
Continuity mistake: The unfortunate Village resident suffocated by Rover is wearing sunglasses that disappear between shots.
Continuity mistake: After Nadia and Number 6 are placed into the packing crate, there's a shipping label on the front. In the next shot, it's vanished. Later, it reappears, but is now on the crate's side.
Chosen answer: We're led to believe Rover is some kind of robot in the series. According to books on the show, Patrick McGoohan was looking for an unusual guardian for the Village, looked up at the sky, and saw a weather balloon, which was what Rover was.
Captain Defenestrator