YMMV / Ken Follett

• Aluminium Christmas Trees: A couple of examples.
  • The First US Army Group (FUSAG) is a World War II military command in Eye of the Needle — but it's a military command that exists on paper only, being part of Operation Fortitude, the Allied counter-intelligence plan to convince the Germans that the D-Day Landings would take place in Calais, not Normandy. It existed as this in Real Life.
  • Readers of A Dangerous Fortune, which is set in the late nineteenth century, may think that a character using the phrase "what the dickens" in 1873 counts as an example of Anachronism Stew, given that Charles Dickens died a mere three years beforehand. However, it's an actually an example of this, as that phrase — an exclamation of confusion — long predates Dickens ^note  quite possibly as an example of Gosh Darn It to Heck!, as it's thought to have originated as a non-blasphemous alternative to "what the devil" ; it was even used by Shakespeare!
• Complete Monster: A few. Micky Miranda in A Dangerous Fortune really stands out — having wheedled is way into the good graces of the Pilaster family's Evil Matriarch, he proves to be the only person capable of manipulating her, and he uses his influence over her and her easily-led son Edward (a Momma's Boy with Depraved Bisexual tendencies that Micky is perfectly willing to exploit) to ensure that the family bank invests in a variety of schemes in his home country, all to the benefit of his own family (and, by extension, himself). A sociopath who enjoys watching acts of cruelty to animals, he treats women as disposable sex objects, uses his Card Sharp skills to utterly discredit a rival, and over the course of the novel commits four murders for which he shows no remorse whatsoever, in addition to which he knows the law can't touch him because he has diplomatic immunity for much of the plot. His murder victims includes the young boy who dies in the prologue; for much of the novel, Edward is convinced that he killed him and the reader is led to believe this as well, but it's eventually revealed that not only did Micky kill him, he then managed to convince Edward that he was responsible for the boy's death, thus establishing the basis for his hold over Edward and, by extension, his otherwise domineering mother.