Continuity: In the opening scene, Gwen has a long, loose strand of hair hanging over her left temple - but every time the camera angle changes, it disappears.

Continuity: When she sees the little boy's ghost, Gwen's hair alternates repeatedly between neatly-combed and windblown/messy, depending on the shot.

Continuity: While she's talking to Mary in the flat, Toshiko's hair keeps changing between shots, going from combed evenly to split apart with one section hanging in the middle of her forehead and the rest brushed back.

Continuity: John is about to eat liver and potato with Emma before she storms out saying, "I don't like liver". While they are talking, the potato is facing Emma and Gwen. After Emma leaves, the liver faces Gwen and the spot where Emma was.

Factual error: Between getting disconnected by the bad guy and calling Ianto, Jack gets a dial tone on the dead man's cell phone. Cell phones don't generate dial tones.

Factual error: When Gwen finds Toshiko's hidden message from 1941, she realizes that it was written in blood, and her flashlight reveals the bright red letters on the now-yellowed piece of paper. But after 60+ years, the iron in the blood would oxidize. The writing on the note should be rust-brown, not red.

Continuity: In the scene on the pier with Toshiko and Tommy, the soldier from WWI, Toshiko is holding her hand bag but drops it when he picks her up. Immediately, the next shot she is holding it again.

Continuity: While he's in the van with Jack, Reese's seat belt shoulder strap vanishes and reappears multiple times as the shots change.

Continuity: When the old man dies and Owen is trying to revive him, the position of the man's head changes several times between takes, from lying flat to propped up on the pillow and back again.

Continuity: When Maggie walks away from the car accident, the blood smears on her white gown change repeatedly from shot to shot.

Factual error: Jack calls Gwen, and when Reese takes the phone and hangs up on him, Jack's cell phone, for the second time in the series, sounds an audible, impossible dial tone.