Revealing mistake: The crossbow a Spaniard uses to shoot the elderly Indian is not loaded with an arrow.
Rendezvous with Yesterday - S1-E1
Character mistake: When Tony talks to captain of Titanic he states he was born in 1938, but in episode 4 "The Day the Sky Fell In" it is December 1941, he should be 3 years old, but as a young child he is about 12 years old.
The Revenge of Robin Hood - S1-E16
Trivia: This episode includes scenes and footage from 1938's "The Adventures of Robin Hood" that starred Errol Flynn.