Stainless Steel Rat Saves the World, The (Stainless Steel Rat Series)

The villainous He has travelled back in time to mankind's distant past on the legendary planet Earth (or 'Dirt') of 1984, where he is altering events so that people who opposed him in the Rat's present cease to exist, Angelina amongst them. Using the Helix, a time-travel device invented by the Special Corps' Professor Coypu, diGriz travels to 1984 America, and then to Napoleonic France where tanks and aircraft are helping bring about Napoleon's victory.