Extract the answer to the following question from the movie plot. If the question isn't answerable, please output "Can't answer". Question: Who is left alone and at the mercy of the "San Francisco Ripper" in this movie? Title: Time After Time Movie plot: In 1893 London, England, popular writer Herbert George "H.G." Wells (Malcolm McDowell) displays a time machine to his skeptical dinner guests. After explaining how it works (including a "non-return key" that keeps the machine at the traveler's destination and a "vaporizing equalizer" that keeps the traveler and machine on equal terms), police constables arrive at the house searching for the serial killer Jack the Ripper. One finds a bag, with blood-stained gloves, belonging to one of Herbert's friends, a surgeon named John Leslie Stevenson (David Warner), whom they are unable to locate in the house, concluding that Stevenson might be the infamous killer. Wells races to his laboratory, but the time machine is gone.Stevenson has escaped to the future, but because he does not have the "non-return" key, it automatically returns to 1893. Herbert uses it to pursue Stevenson to November 5, 1979, where the machine has ended up on display at a museum in San Francisco realizing that due to the machine traveling backwards by the geographic longitide and latitude, the machine had ended up in the unfamiliar USA.As Herbert walks around the city, he is deeply shocked by the future, having expected it to be an enlightened socialist utopia, only to find chaos in the form of airplanes, automobiles and a worldwide history of war, crime and bloodshed.Searching numerous banks for Stevenson - he believes an Englishman might need to exchange old currency - Herbert meets liberated Chartered Bank of London employee Amy Robbins (Mary Steenburgen). She directs Herbert to the Hyatt Regency hotel, as she previously had Stevenson.Confronted in his room by his onetime friend Herbert, Stevenson confesses that he finds modern society to be pleasingly violent. Apologetically, he states: "Ninety years ago, I was a freak. Now... I'm an amateur." Herbert demands he return with him to 1893 to face justice, but Stevenson, who without the "return key" would be unable to prevent the machine from automatically returning (and thereby blocking Herbert...
Answer:
Can't answer