Nearly every time travel theory offered by physicists, such as black holes, wormholes, or multiple universes, has been taken up by storytellers. Time travel gives good box office; Arnold Schwarzenegger will reportedly get $30 million to star in the third Terminator film. Time travel makes for a nifty plot device, a catalyst that works across genres, including comedy, romance, horror, fantasy, and detective story; in the film Time after Time, H.G. Wells himself chases Jack the Ripper through 1970s San Francisco. In print, Bradbury, Dick, Heinlein, and their successors filled the shelves with time-travel variations. But the greatest success may have come to a romance writer. Diana Gabaldon has reached the bestseller lists several times by sending the 20th century heroine of her Outlander bodice-ripper novels into the arms of 18th-century hunky Scotsman Jamie Fraser.