Gunsmoke got a whole lot more colorful when its twelfth season debuted Sept. 17, 1966. For the first time, the adventures of Marshal Matt Dillon, Miss Kitty, Doc, Festus, and the gang would be broadcast in color, requiring some big changes for its actors, their costumes, and the Gunsmoke intro.

Here’s what happened when Gunsmoke debuted its first color episode, “Snap Decision,” which sees Marshal Dillon in a major crisis.

According to Amanda Blake, who played Miss Kitty, no real changes happened on the Gunsmoke sets, which she said merely served “as a frame for the characters.” But her character literally underwent an overhaul from head to toe.