And what River Cartwright is thinking is that rewriting history is the Service’s favourite game; a topic he might illustrate from a hundred of the O.B.’s late-night stories, but which is most immediately realized for him in the fact of Sidonie Baker’s absence — not merely from the office, but from the records of the hospital in which she supposedly died, which have been so thoroughly sanitized as to offer reassurance as to the hygiene standards of the NHS. Just as she is not here now, so she was never there then. Indeed, River’s own memories and those of his colleagues aside, his only absolute proof of her having existed resides in the barrette he found in his car, and which he has placed on her desk. As for proof of her having ceased to exist, he has none. Which allows him to speculate — or perhaps a better word might be pretend — that what he imagined happened to her did not.
— Slow Horses (Mick Herron), Loc. 5781–7