The show featured guests (played by actors) who played significant roles in world history. Guests would interact with each other and host Steve Allen, discussing philosophy, religion, history, science, and many other topics.
As nearly as was possible, the actual words of the historical figures were used. The show was fully scripted (yet the scripts were carefully crafted to give the appearance of spontaneous discussion among historic figures who, in real life, would have at most known of each other by reputation). Guests included: Plato, Socrates, Aristotle, Thomas Aquinas, Cleopatra, Marie Antoinette, Florence Nightingale, Thomas Paine, Francis Bacon, Thomas Jefferson, Voltaire and Charles Darwin.
Typically, each episode would be split into two parts, broadcast separately, with most or all of the guests introduced over the course of the first part, and the discussions continuing into the second part.
Frequently, actors would make multiple appearances as different guests, over the course of the series; this was particularly true of Allen's wife, Jayne Meadows. There was also one major departure from the usual format, in which William Shakespeare was joined by several characters from his plays, with Meadows playing the role of the "dark lady" of his sonnets.
The scripts are available for public performance. Because of their educational nature, Allen did not attach a royalty to such performances.