Jack Webb offered this judgment of Harry Morgan's acting while filming Dragnet
Webb preferred a "flat" acting style.
As an actor, producer, director, and writer, Jack Webb truly had his finger on the pulse of what viewers were interested in watching. Webb became famous for a variety of shows, including multiple iterations of Dragnet, which he also starred in. As both a performer and a creator, Webb had the interesting perspective of seeing the show from two different viewpoints and was able to perform his job extraordinarily in both, according to his former costar.
According to an interview with the San Francisco Examiner, Henry Morgan, best known as Bill Gannon, explained that even with the realm of control Webb exercised over the production, Morgan didn't feel constrained in his role.
The actor said, "Not really. Maybe I'll want to change a line of dialogue so it reads easier, but Jack doesn't object to that." There was just one cause for difficulty on set toward the beginning of production. Morgan said that originally, Webb didn't agree with the direction he was taking Bill Gannon in, performance-wise, and felt that Morgan's portrayal was too heavy-handed.
Morgan said, "I wasn't playing Gannon the way Jack wanted me to. I was acting too much. That's a style Jack doesn't like. He doesn't want you to act. He wants you to be flat. No projection. Just stand there and read lines."
Despite the criticism, Morgan and Webb got along well together, both on-screen and off. Both men frequently spoke highly of one another and made an excellent duo.

