James Marsden has joined the cast of “Robot & Frank” starring Frank Langella and Susan Sarandon.Pic will be directed by Jake Schreier and also stars Jeremy Strong, Liv Tyler and Liev Schrieber as the voice of a caretaker robot. Langella plays a curmudgeonly lover of books whose only friend is a librarian (Sarandon). He leads a lonely life until his grown children install a robot to care for him, sparking off an unlikely friendship. Marsden will play one of the children. Christopher Ford penned the script and Galt Niederhoffer and Sam Bisbee are producing. Marsden was most recently seen in the Universal pic “Hop.” He is repped by WME and Brillstein.