Twenty years since the release of the classic thriller Speed starring Keanu Reeves, the Avengers director Joss Whedon has spoken for the first time about writing the majority of the dialogue for the movie, despite not receiving a writing credit. 

Joss WhedonJoss Whedon wrote the dialogue in Speed, you know.

The movie, which made over $300 million at the box-office, was officially written by Graham Yost, the screenwriter who has since worked on Band of Brothers and Justified - though he's regularly cited Whedon's influence on the script.

Now, in a new interview with the Huffington Post, Whedon spoke about working on the movie, saying he has the only poster which bears his name.

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"In my whole career, I've never had to talk about it" he said, "I've never signed a copy of it, I've never sort of been a part of it. And I was proud of it, I worked hard on it, I had a really great time and I worked with really cool people. I thought it was good stuff. Graham has been very generous, but I did not get a credit on it. The studio gave me one, but then the Writers Guild of America took it away, and I was pretty devastated. I have the only poster with my credit on it."

Whedon said the removal of his credit was "to do with WGA bylaws," adding, "You can come in and rewrite all of the dialogue, and still not get credit. They didn't think I made big enough changes to the plot. I actually did a lot of overhaul, but much of it was to a later draft, so it went back to what Graham originally had."

Yost credits Whedon with most of the movies dialogue and says most of the more ridiculous scenes only work because of the lines that the Avengers man wrote.

"There was a draft - after Graham's, before I came on - that was very not good. One of the things it had in it was that Sandra Bullock's character was a stand-up comic, and I'm like, "Nobody can ever root for a stand-up comic in this kind of movie!"

Neither Whedon nor Yost were involved in the sequel Speed 2: Cruise Control - considered one of the worst movies of all time.

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