Sam Rockwell is joining Scarlett Johansson in Jojo Rabbit Oscar winner Sam Rockwell (Three Billboards Outside Ebbing, Missouri) is reteaming with his Iron Man 2 co-star Scarlett Johansson for the upcoming Fox Searchlight film Jojo Rabbit, according to The Hollywood Reporter. The movie is about Jojo, a young boy who longs to be part of the Hitler Youth and whose imaginary friend is Adolph Hitler.