Jesse Eisenberg and Jeremy Irons have joined the cast of 'Batman/Superman'.

'The Social Network' star Eisenberg will play Supervillain Lex Luthor in the forthcoming movie, which will see Batman and Superman appear together in the same movie for the first time.

Director Zack Snyder said: ''Lex Luthor is often considered the most notorious of Superman's rivals, his unsavoury reputation preceding him since 1940.

''He's a complicated and sophisticated character whose intellect, wealth and prominence position him as one of the few mortals able to challenge the incredible might of Superman. Having Jesse in the role allows us to explore that interesting dynamic, and also take the character in some new and unexpected directions.''

English actor Irons will play Alfred, butler and closest ally to Batman, who will be embodied by Ben Affleck for the fist time in the upcoming film.

Snyder added: ''As everyone knows, Alfred is Bruce Wayne's most trusted friend ... a noble guardian and father figure. He is an absolutely critical element in the intricate infrastructure that allows Bruce Wayne to transform himself into Batman. It is an honour to have such an amazingly seasoned and gifted actor as Jeremy taking on [this] important role.''

Henry Cavill will reprise his role as Superman, and the movie - which is yet to be properly titled - is in the pre-production with an expected release date in May 2016.