Ryan Reynolds nervous about playing Pikachu

Ryan Reynolds was nervous about joining the cast of 'Pokemon: Detective Pikachu'.

The 42-year-old actor voices the beloved Pokemon character Pikachu in the new movie and he admitted that the popularity of the gaming franchise left him worried about doing it justice.

Speaking to The Hollywood Reporter, he said: "You're sort of grappling with this beast. There's a reason that Pokemon's been a worldwide cultural phenomenon for so long and people are so passionate about it. But it was a great story and it worked whether you had Pokemon in it or not."

And director Rob Letterman admitted he was also worried about getting the story right for the fans.

He said: "I'm nervous right now. I always am nervous. It's something that people care a lot about; that people grew up on around the world. We put a lot of care and love into making sure it was right. And we worked very closely with the original creators in Japan to make sure we got it right."

And Letterman knew Ryan was perfect for the role when he took a clip of the star from 'The Proposal' and placed his voice over an animated Pikachu.

He said: "Once I saw that clip, I was done. It's a really hard thing to do. It really narrows down who can play that character. We wanted somebody with a big personality who could come out of this adorable, little character. But they also had to have heart."

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