Character mistake: On the witness stand, Janet Wilk speaks of moving "here to Lincoln City", but the episode takes place in Jackson City.
Character mistake: Voice on the radio says a 39-year-old with a gunshot to the left shoulder; however, Will was shot in the right shoulder. (00:40:13)
Six Forgotten Warriors Chapter 4: The Six Fight Again - S5-E5
Character mistake: When the Red Skull reemerges from the vortex, he sees Chameleon and acknowledges him as his stepson. However, only moments before this, Kragov explicitly stated that the Chameleon was more like an adopted son to the Red Skull.
Devil Music - S5-E4
Character mistake: When they pulled the bullet out of the wall of the Five and Dime, Danny says that it was either a .40 or .45 caliber. The .40 caliber was not produced until 1990, 37 years after the date the crime took place. (00:30:00 - 00:35:00)
Character mistake: The X-ray shown when Ruth see Cade's body is placed in the wrong way. It should have been a mirror image. (00:57:56 - 00:59:06)
Character mistake: When Rich refers to the film showing Davis (decades ago), he figures they were in "Asia... Mongolia or somewhere." However, the film cannister had "Tibet, 1937" written on it - important enough to show the audience, but not for the character to read? (00:40:25)
Character mistake: The note Six hands the "access man" misspells the word "receipt" as "reciept." He's supposedly a "think tank" genius, so really should be able to spell better than that. (00:27:30)
The New and Improved Carl Morrissey - S1-E2
Character mistake: The advertising leaflet for the cemetery misspells it "cemetary" on the front cover.
Episode #4.4 - S4-E4
Character mistake: A computer screen giving details of the villain of the week contains various spelling and grammatical errors: "Embassey", "Assination" and "Assination of with".
Character mistake: Jaden tells Damon that because of Elemental Hero Flame Wingman's ability, he will lose life points equal to half his destroyed monster's attack points. This is incorrect, as Damon will actually lose life points equal to the full attack points of the destroyed monster. He has used this card multiple times throughout the series, so this isn't a mistake he should have made. (00:18:25)
Angel of Mercy: Part Two - S1-E4
Character mistake: When Lenore Osgood is speaking on the phone with Charles Wainwright about killing Dr. Hanover, she mispronounces "Larynx" as "Lar-nix."
Episode #1.1 - S1-E1
Character mistake: In the subtitles, Halcrow mentions a German company as 'Unternehme'. The right spelling of this German word is 'Unternehmen'. (00:46:35)
Character mistake: Joe called Cruz a Sergeant First Class (E-7), which is a US Army rank. It was established in Season 1 that Cruz is in the US Marine Corps, so she would be a Gunnery Sergeant (E-7). (00:19:48)
Character mistake: In the epilogue, Charlie illustrates the relationship of mathematics to real life by discussing the golden ratio and its presence in a host of real-life situations, including the shape of a nautilus shell and the distribution of petals in a flower. These claims are disputed by some mathematicians (see http://en.wikipedia.org/wiki/Golden_ratio#Nature), and the one about the nautilus shell one is untrue (see http://en.wikipedia.org/wiki/Golden_spiral#Spirals_in_nature). It's possible Charlie is just repeating what he has read or heard without investigating it for himself, but this is uncharacteristic of him.
The Night of the Skulls - S2-E13
Character mistake: There are seven mourners dressed in black surrounding Gordon's casket - three on each side and one by the funeral officiator (who is the disguised Gordon). Later in the scene when West is talking to the disguised Gordon, Gordon says, "How do you like that - six mourners..." (00:05:20 - 00:07:10)
Episode #2.3 - S2-E3
Character mistake: DS Maxwell comes to Katy's house to interview her but when he introduces himself he says "DI" Maxwell.
Character mistake: Sam describes the books as being from "pre-Biblical lore" and then says they are written in Aramaic. Aramaic was a language during New Testament Biblical times and didn't exist in pre-Biblical times i.e. prior to 4000 B.C.E.
Suggested correction: I believe he meant the book "contained" pre-biblical lore.
Character mistake: Upon finding the Spanish flu virus missing, Hardison freaks out about it killing 50m people 100 years ago, saying it would be even more deadly today due to the higher population. There's no reason to think so - the death toll in 1918 was massively exacerbated by the aftermath of WWI. Not to mention today we have vaccines, plus most deaths then were actually caused by bacterial pneumonia, which today is easily treated with antibiotics.
Episode #5.3 - S5-E3
Character mistake: The chief baddie spells definitely as definately.