Overexcitable publishers like to bandy around words such as "explosive" and "shocking" when trying to flog their books, even though generally you could substitute them for ones such as "mildly interesting."
UNDERCOVER: The True Story of Britain's Secret Police, by Paul Lewis and Rob Evans. Faber and Faber, 2013, 352 pp., £12.99 (paperback)
Not with "Undercover," though. Subtitled "The True Story of Britain's Secret Police," and doggedly written and researched by Guardian journalists Rob Evans and Paul Lewis, the revelations in its pages are genuinely explosive. And even though a lot of the material was in the news, reading it line by line, deception by deception, is genuinely shocking.