That same year, deHavilland was re-united with Flynn in their sixth film together, Michael Curtiz's Western adventure "Santa Fe Trail", set against the backdrop of abolitionist John Brown's fanatical anti-slavery attacks in the days leading up to the American Civil War. The mostly fictional story follows West Point cadets J. E. B. Stuart, played by Flynn, and George Armstrong Custer, played by Ronald Reagan, as they make their way west, both vying for the affection of deHavilland's Kit Carson Halliday. Playing Kit in a provocative, tongue-in-cheek manner, deHavilland creates a character of real substance and dimension, according to Tony Thomas. Following a world premiere on December 13, 1940, at the Lensic Theatre in Santa Fe, New Mexicoattended by cast members, reporters, the governor, and over 60,000 fans "Santa Fe Trail" became one of the top-grossing films of 1940. DeHavilland, who accompanied Flynn on the well-publicised train ride to Santa Fe, did not attend the premiere, having been diagnosed with appendicitis that morning and rushed into surgery.