 Joss Whedon (qv) wrote a draft version of the script, but the  suggestions he made to fix what he felt were fundamental problems  with the film were not incorporated. Only two pieces of dialogue  from his rewrite appeared in the final film. One is the exchange  when Cyclops doesnt know if Wolverine is an impostor ("Prove it!"  "Youre a dick"); the other is Storms "Do you know what happens  when a toad gets hit by lightning? The same thing that happens to  everything else." which he imagined as a lighthearted, offhand line.