Simplify the following text for a Grade 8 native English-speaking person.
Original: In 1967 , he was the most successful draw at the box office , the commercial peak of his career , with three successful films , Guess Who 's Coming to Dinner ; To Sir , with Love and In the Heat of the Night .
Simplified: In 1967 , he was the most successful actor at the box office , with three successful films , Guess Who 's Coming to Dinner ; To Sir , with Love and In the Heat of the Night .