Karen Allen wrote to Indiana Jones and the Dial of Destiny director and producer Kathleen Kennedy to tell them her character Marion Ravenwood should appear in the sequel.

The 73-year-old actress played Indy's love interest Marion Ravenwood in the original 1981 film Raiders of the Lost Ark and the 2008 sequel Indiana Jones and the Kingdom of the Crystal Skull and was set for a significant role in Disney's fifth film, released in 2023, when Steven Spielberg - who helmed the previous four films - was set to direct from a script by David Koepp.

However, when James Mangold took over as director and decided to change the script with a new team of writers aiding Koepp, he decided he didn't want the movie to focus on Indy's relationship with Marion, and so Karen took it upon herself to tell him and Kennedy that they were making a "terrible mistake".

Speaking on a panel at Terrificon, she recalled: "When Steven was going to direct, I was majorly [featured]. It was about us, Indy and Marion.

"But then when he stepped to the side, and they went off in a different direction - I think I can say this now because it's been some time - I wasn't in the original script that they finished when James Mangold [took over].

"When he finished the script, I wasn't in it at all. It was communicated to me, and I said, 'You're making a terrible mistake.'"

The National Lampoon's Animal House star - who didn't appear in 1984 prequel film Temple of Doom nor 1989 adventure The Last Crusade, which paired Harrison Ford as Indy with his father Henry Jones Sr. played by the late Sean Connery - penned a letter explaining why it was important for Marion to feature in what has been billed as Ford's last outing as the daredevil archaeologist.

Revealing the contents of the letter, Karen added: "'You're making a terrible mistake. Marion is such a vital, interesting, wonderful character you created, you can't just let her disappear into the ether.'

"And I got a phone call the next day and Kathy Kennedy said, 'You're absolutely right. I don't know why we thought it was okay to do that.'"

In the final film, Karen appears as Indy's wife Marion in a scene that reunites them and ends their journey.