In the series premiere, Sam has theorized the ability to travel in one's own lifetime and is the lead scientist of the government-funded Project Quantum Leap, operating from a secret laboratory in New Mexico; Al oversees the project for the government. When Al learns that funding for the project is in danger of being pulled because no demonstrable results have come from the project, Sam takes it upon himself to step into the Quantum Leap accelerator to prove that the project works; unfortunately, he does this well before the project is ready to be demonstrated, and is sent into the past. When Sam gains consciousness, he finds himself suffering from partial amnesia, and is more surprised to find that his appearance to others, including what he sees in the mirror, is not his own face. He finds that Al has come to his aid as a hologram that only Sam can see and hear, as it is tuned to his brainwaves. Al, working with the project's artificial intelligence Ziggy (voiced by Deborah Pratt), determines that Sam must alter an event in the current period he is in so as to re-engage the Quantum Leap process and return home. Al helps Sam overcome some facets of his "Swiss-cheese memory" and provides information on history as it originally happened. He also updates Sam on future events and relates possible outcome-probabilities using a handheld communication device in contact with Ziggy. The device is often temperamental and must be struck a few times as it emits electronic beeping and whirring sounds before the information is revealed. With Al and Ziggy's help, Sam is able to successfully change history, and then leaps out, only to find himself in the life of someone else in a different period of time.