My mother was a great fan of the theater. She saw Paul Robeson play Othello and said he was stiff. Robeson made a couple of movies, and I've seen them, and mom was right. His delivery is kind of wooden, without much emotion.
Said a friend of mine, "Well of course he was stiff, but you heard that deep voice and you just fell in."
But how that man could sing!!
There's a 1930s version of "King Solomon's Mines" in which Robeson plays an African prince. He doesn't talk much, but he sings! It's worth all the silliness for that voice. You do fall in.