Legend has it that Billy the Kid shot and killed 21 men; one for each year of his life. The legendary outlaw's own life was taken sometime after midnight on July 14, 1881, by the reformed lawman Pat Garrett in Fort Sumner, New Mexico. There is still speculation that Garrett, a longtime acquaintance of Billy's (whose birth name was Henry McCarty) never actually shot down his old friend and allowed him to escape in the dark of night.

Garrett was also accused of ambushing McCarty, which led to him hiring a ghost writer named Marshall Upton who detailed Garrett's version in "The Authentic Life of Billy, the Kid." The book has become a great historical reference, but at the time of its release in 1882, it failed to change the popular opinion that Garrett may have acted ungentlemanly the night Billy the Kid was slain.

Most Westerns don't ever get a sequel, but the surprise success of "Young Guns" led to "Young Guns II" in 1990 with the returning cast of up-and-coming talent featuring Lou Diamond Phillips, Keifer Sutherland, and Emilio Estevez as Billy the Kid in a career-defining role. "Young Guns II" told the story of how Pat Garrett (played wonderfully by William Peterson) tracked down Billy in the Old West, while also following an elderly man in the late 1940s named Brushy Bill Roberts, who claimed he was Billy the Kid until the day he died.

Peterson's stoic version of Garrett contrasted perfectly with the unbridled energy of Estevez, resulting in some great onscreen clashes as Garrett methodically tracks the infamous fugitive down. Every actor in a Western has a story about a horse, and Peterson was no different. On set, he fell in love with a buckskin-colored steed that wound up stealing the show.

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Most actors just make up the fact that they can ride a horse during the audition process for a Western. The skills section on an acting resumé is generally considered to be widely exaggerated. For William Peterson, who was mostly known as a streetwise detective in Michael Mann's "Manhunter," it was important to find a horse that he actually felt comfortable with when he landed the role of Pat Garrett and suddenly found himself on the harsh, open plains of Arizona and New Mexico.

During filming, each horse had a double that was also used, but Peterson could tell the two apart and took a real liking to one horse in particular. NBC5 reporter Bobbie Wygant's incredibly vast archive of vintage interviews features a conversation with Peterson, who talked about how he kept trying to get his favorite stallion in the shot:

"They'd bring the horse to me and I had to do this whole thing with this horse to figure out which horse it was. I actually knew, and then I would try and sneak the other horse out of the corral and saddle him up and get on him before the wranglers knew that I had the other horse, because I liked him so much."

Peterson claims his horse made it into a lot of the finished film, becoming "a little movie star." Interestingly, actor James Coburn — who played Pat Garrett in Sam Peckinpah's "Pat Garrett and Billy the Kid" opposite Kris Kristofferson — plays a rich cattle owner named John Chisum in "Young Guns II." Williamson also mentions that he spoke to Coburn at length about both of their takes on the real-life lawman.

If "Young Guns III" ever happens, maybe Peterson can return in some capacity. At least bring Bon Jovi back!

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