Former scientist Sam Beckett finds himself trapped in time due to an experiment gone awry, leaping into the body of a different person each week. Al Calavicci, at first known only as The Observer, is Sam's holographic adviser - he provides Sam with some details about his new identity and gives him guidance on how to help the people affected by his presence. But with little memory to help guide him, our hero is forced to bluff his way through many a wacky situation.