Although a sequel to the smash hit 'Sin City' at one time seemed like it was on the fast track, fans have become discouraged by delays and negative talk that suggests the sequel may not happen. Frank Miller wants to set the record straight. There will be a 'Sin City 2'."There was just some problems above us that I don't understand...that I don't really want to understand," Miller tol MTV Movie Blogs matter of factly about studio delays in pre-production. All of which shouldn't bum out fans, he insisted, since he expects not only to eventually film 'Sin City 2,' but 'Sin City 3' as well. That story, Rodriguez divulged, would concentrate on Miller's 'Hell and Back,' the story of a hallucinating artist named Wallace. Rumors have persisted for months that the role of Wallace was being written for Johnny Depp, a casting coup that Rodriguez himself was coyly confident would eventually happen.