Both Bruce Willis and Samuel L. Jackson were touted to play crooked narcotics detective Alonzo Harris prior to Denzel Washington signing on for what would become his second Oscar-winning role.
Ethan Hawke was one of several actors to have screen tested alongside lead Washington for the role of rookie cop Jake Hoyt - that list included Tobey Maguire, Freddie Prinze Jr., Paul Walker, and Ryan Philippe.
But at one point in development, Washington and Hawke were to be joined by a more unexpected co-star: Eminem, who almost signed up to make his movie debut as one of the seedier supporting characters.
In the years since, movie legend has been rewritten to claim that Marshall Mathers was up for the role of Jake Hoyt - but in actuality, it was a villainous part more suited to his controversial stage persona.
If the rapper had taken the plunge, he would have starred alongside his regular collaborator Dr Dre. Instead, he turned down the project to focus on developing 8 Mile instead.
Before Slim Shady finally made his jump to the big screen, he was offered several other Hollywood roles too, including Brian O'Connor in The Fast And The Furious, a part that eventually went to Paul Walker.
His ties to that character didn't end there either, as Eminem was the first person approached to make See You Again, the Walker tribute song that plays in 2015's Fast 7.
As a further odd coincidence, Wiz Khalifa and Charlie Puth's track went on to rival Eminem's own Lose Yourself spending 12 weeks at number one on the Billboard Hot 100.
In the years since, Eminem has been offered several major roles he turned down too, including the lead in sci-fi Elysium (which went to Matt Damon), and two separate boxing dramas: Southpaw (which went on to cast Jake Gyllenhaal, despite being written for Em) and Mark Wahlberg's understated lead role in The Fighter.
Most incredibly of all, Eminem was also rumoured to have been eyed up to play Batman in an early 2000s reboot of the franchise entitled Batman V. Superman: Asylum.
Alas, that project was cancelled after spending years in development hell, with Christopher Nolan taking over the franchise and eventually casting Christian Bale as his Dark Knight.
We know Eminem can act - but it's still strange to think that we would likely think of him as more of a movie star than a rapper if he'd taken on some of these roles.
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