Has Fallen's Mike Banning would make a great member of The Expendables - here's how it could happen. While R-rated action movies used to be big business, especially during the '80s and '90s, the success of comic book movies and action franchises like the Fast & Furious saga saw mainstream event movies gradually lean towards PG-13 instead. There are notable exceptions, such as The Expendables series, which was designed specifically to appeal to a more retro sensibility and unite icons from that era like Sylvester Stallone, Arnold Schwarzenegger and Jet Li.

Another is the Has Fallen franchise, which kicked off with 2013's Olympus Has Fallen. This famously arrived the same year as White House Down, with both being action thrillers where a character has to save the President from a takeover of the White House. Olympus Has Fallen won that particular fight, with Gerard Butler's Mike Banning proving a hit with viewers for his blunt approach to saving the day. Banning then became the head of a surprise franchise, returning for 2016's London Has Fallen and Angel Has Fallen.

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Butler is set to return once again for the upcoming Night Has Fallen, though that sequel's story has yet to be announced. Following the disappointment of the third entry in 2014, The Expendables series is finally dusting itself with a forthcoming fourth outing. While Stallone's Expendables movies are silly fun at their best, there's a sense they've run out of action legends to add to the cast, and they could use a new approach to keep things fresh. Considering that Millennium Media owns both the Has Fallen series and Expendables, maybe Mike Banning himself should make the leap to join the latter group for one entry.

To date, neither franchise has featured any crossover in terms of major cast members, and there's nothing to say they can't exist in the same world. The Has Fallen movies have, on the whole, featured a more grounded tone, but they're not that far apart on that front either. Banning himself is an ex-Army Ranger who was shown to have some ties to mercenaries - who turn out to be villainous - in Angel Has Fallen, so it's not stretch in logic he could know Stallone's Barney or another member of the Expendables line-up and call on them for help in a crossover movie.

Banning could even battle against them until they need to unite against a common foe if the movie wanted to play around first. One of the best sections of London Has Fallen - which is typically considered the weakest outing - has Banning battle alongside a joint Delta/SAS extraction unit, so lone wolf Mike has been shown to work well in a team too. Since Has Fallen's Banning is a family man it seems unlikely he would just quit his Secret Service job to become a hardened merc, but it wouldn't be difficult to find a scenario where he would have to fight with them either, such as a dangerous rescue mission. Mixing The Expendables and the Has Fallen movies would be Millennium Media's best crossover since series like Rambo or Undisputed do share certain cast, but while there's no sign of it happening, it's a fun concept to think about.

Next: Night Has Fallen Should Make Gerard Butler's Banning The Next President