She'll join Charlie Hunnam at the Round TableWhile Guy Ritchie’s King Arthur film promises to be loaded with testosterone thanks to its knight-heavy ensemble, there will be at least one balancing female presence in the group. Deadline reports that Pirates Of The Caribbean: On Stranger Tides’ mermaid Astrid Berges-Frisbey has been cast as Guinevere.Ritchie is currently filling his cast for the film, which Warner Bros.