The Time Traders 时光商人
At the end of this century Ross Murdock is given the choice between prison and a dangerous role in a secret mission. Accepting the latter, but determined to escape at the first opportunity, the intelligent young man finds himself involved in a project which demands that he be projected back to various periods in history. For the Americans, aware that the Russians, somewhere in time, have learned the secret of space travel, must for the sake of national safety, obtain the same secret.