When the leader of the Expansionist Party, John Bonforte, is kidnapped, unemployed actor Lorenzo Smythe is hired to take his place just before an important ceremony that will serve as a peace treaty between Mars and Earth. Should he fail, however, the results could be interplanetary war.

While the resemblance between Lorenzo and Bonforte is remarkable, the actor undergoes intense training to learn the politician’s background, thought process, manner of speech, and body language as well as the Martian phrases he must utter with impeccable precision during the ceremony. Coached by Bonforte’s team, Lorenzo delivers a flawless performance.

Shortly after, the real John Bonforte is found, but his mind and memories have been scrambled, leaving him in no condition to resume his responsibilities until he is fully recovered. Even his personal physician is uncertain how long that will take. Thus, Lorenzo must continue his impersonation, fearing that at any moment, the charade will be revealed.

As one of my favorite Heinlein novels, Double Star is a thoroughly entertaining, fast-paced romp with likeable characters, witty dialogue, and constant tension.