'Yesterday, Today and Tomorrow' is the climax of John Joyce's 'Virtual Trilogy' of cyberthrillers following the quest by billionaire genius Theo Gilkrensky to save his beloved wife Maria from murder by warping the fabric of time. Convinced that the research he carried out in 'Virtually Maria' and 'A Matter of Time' will enable him to jump back in time and save Maria from death, Theo travels to Japan and enters into a pact with his greatest enemies to obtain the computer power he needs to complete his calculations. But dark forces are massing to destroy him. Yukiko Funakoshi,the seductive assassin who blames Theo for the death of her parents recruits a gang of former terrorists to commit the ultimate act of revenge. The CIA are out to arrest him for industrial espionage. And even the faithful Minerva 3000 computer, whose artificially intelligent user-interface programme has been fashioned to look, sound and act like his late wife, is plotting against him. From the infinite horizons of cyberspace - to the depths of the human heart, the final battle for 'Yesterday, Today and Tomorrow' is about to begin.