Factual error: Spoiler alert - When Henry's body is recovered under the 4th Street Bridge in Los Angeles, the 6th street bridge and the 7th street bridge (the one that he fell off) are each visible in the background. Meanwhile the water is visible moving towards the 7th street bridge which indicates that his corpse floated against the current. (00:22:20)
Factual error: On the plane, Emma shows an issue of Hello! magazine featuring the heiress Grace is passing as. It's labeled as "number 1100, May 31 2010", but the May 31 2010 issue was actually number 1125. (00:30:30)
Factual error: The car doors wouldn't protect Adam and the other police officers from being shot - they offer no protection against bullets.
Factual error: Mallory tells Florence that the school is in Cumbria. Cumbria didn't exist in 1921. It was created in 1974 from Cumberland, Westmorland and part of Lancashire.
Factual error: Jerry digs up a natural gas pipeline in the backyard and jerks it so hard that a pipe coupling in Charlie's house breaks, venting natural gas into the house for about 4 seconds. Then Jerry uses a cigarette lighter to send a flame through the pipeline, exploding Charlie's house like a fire bomb, catching virtually every room in the house on fire. In reality, it would take an hour or more for vented natural gas to accumulate sufficiently to blow up a house, for one thing. For another thing, Jerry broke the gas pipeline in the backyard in order to ignite it; so, while the broken pipeline leading to Charlie's house had no gas pressure, the pressurized side of the pipeline was still in the backyard with Jerry. Meaning, Jerry himself should have been engulfed in fire as soon as he sparked a flame.
Factual error: The term mayor of Paris was abolished from 1871 till 1977. But we see Victor Maynott wants to join the mayor campaign in 1910.
Factual error: Rochester Castle is seen standing alone and isolated from any other settlement. In actual fact it stands on the edge of the City of Rochester and very close to Rochester Cathedral, both of which certainly existed at this time.
Factual error: In the medicine cabinet, when Margaret is emptying it, a box of Rite-Aid Bandages is visible. Rite-Aid is an American chain of drug stores, not in the UK. And the Brits call the product plasters.
Factual error: Lady Arabella mentions her ex having put their "private" tape on Youtube. Impossible as Youtube strictly forbids that sort of thing from being uploaded on their site.