Dinklage and Dornan co-star in the new HBO movie My Dinner with Hervé. The pair were on the film's set when they read as Fifty Shades characters Anastasia Steele and Christian Grey, respectively.
"I read some of the screenplay, though, in our dressing room," Dinklage recalled. "I went in, he had to do some reshoots for Fifty Shades and I would help him out learning lines."
"I would read the Dakota Johnson parts," he added, referencing Dornan's co-star. "I was just helping a friend learn lines. I nailed it. I really did."
My Dinner with Hervé explores the unlikely friendship between late actor Hervé Villechaize (Dinklage) and struggling journalist Danny Tate (Dornan). Tate interviewed Villechaize days before the actor's suicide in September 1993.
"They realized they had so many things that paralleled," Dornan said of Villechaize and Tate's bond in an interview with USA Today.
"They were both dealing with very similar things and destructive elements of their characters," he added.
My Dinner with Hervé premieres Saturday. Dinklage is also known for playing Tyrion Lannister in the HBO series Game of Thrones, which will return for an eighth and final season in 2019.