In film, other actors' performances really are not your concern. If the other actor isn't giving you what you want, act as though he were.
Michael CaineI heard my first laughter on stage, when I was about 10 years old. It was gold pantomime and I remember I was playing Baron Fitznoodle, who was the father of the ugly sisters in "Cinderella." And I walked on and got a great big laugh and I thought that was fantastic, until I looked down and found that my flies were open. And so I always check my flies. I even check my flies on radio.
Michael Caine