'Zombieland 2': Rolling Stones rocker Keith Richards, 'Ghostbusters' cast originally planned for film's big cameos

Warning: Zombieland: Double Tap spoilers ahead.

A sequel to the 2009 sleeper hit Zombieland was greenlit almost immediately after that film's initial success, and screenwriters Rhett Reese and Paul Wernick cranked out a screenplay for it within six months of opening.

Due to several factors, though, that sequel never came to be, and it wasn't until this past weekend – almost exactly a decade after the first film opened — that a follow-up, Zombieland: Double Tap, finally hit theaters.

In a wide-ranging sit-down with Yahoo Entertainment, Reese and Wernick revealed what that original script looked like, including the ambitious celebrity cameo they had planned.

"There was a Rolling Stones cameo, a Keith Richards cameo," Wernick said (watch above).

In the first draft, the RV that the gang briefly commandeers was going to be an abandoned tour bus for the seminal rock group. "It was in Los Angeles outside the Staples Center and they saw it and they were like, 'Oh my God, we gotta get the Rolling Stones tour bus,'" Reese explained. "So they went in there and I believe Keith Richards was alive and holed up, but they mistook him for a zombie and shot him."

In other words, Richards would have been the film's new Bill Murray, who was so famously killed in the original when Columbus (Jesse Eisenberg) took him for zombie. He was wearing full zombie makeup to fit in, after all.

But this one had a twist: "He wasn't dressed as a zombie," Wernick said of the now-75-year-old rock icon lovingly known for his haggard looks. "He looked like himself."

When Reese and Wernick picked back up on the project in more recent years, they realized that returning Murray to sequel was a necessity. They just needed to figure out how they'd bring him back, considering he was deceased in the Zombieland universe.

While in the final product, an end credits scene shows the zombie outbreak first hitting the press junket for Murray's Garfield 3: Flabby Tabby, early drafts had him golfing with Dan AykroydHarold Ramis and Ernie Hudson, who were all attempting to convince Murray to make Ghostbusters 3 when the virus hit.

"Then Dan Aykroyd becomes a zombie, and they have this battle royale out on the golf course," Wernick explained, adding that the scene also included a Joe Pesci cameo. "And then Ghostbusters [the 2016 female-lead reboot] came out. Bill Murray was in it, [so] we had to toss that, and that evolved into the Garfield 3: Flabby Tabby cameo."

Zombieland: Double Tap is now in theaters.

Watch our complete interview with Reese and Wernick:

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