At the briefing, Jim fires 4 shots next to Rollin's Ear. After the 4th shot, Jim asks if he heard the shots and Rollin says " No, just you counting." But whilst Jim was shooting the gun, Rollin's eye twitch after each shot.
John Colicos, Charles Maxwell and Barry Atwater played roles in three different "Star Trek" shows. Colicos played Commander Kor in "Errand of Mercy", Maxwell played Virgil Earp in "Spectre of the Gun" and Atwater played Surak in "The Savage Curtain".