Movie character Robert Mueller reminds me of-

[heckles65]

-- FBI Agent Sheldon in "Dog Day Afternoon."

Grandstanding bank robber Sonny (Al Pacino) was able to chum with NYC police detective played by Charles Durning. But as the afternoon turns into evening, Sheldon takes over, and he isn't going to give Sonny and his accomplice an inch more than he has to. Sheldon has the electricity - and the air conditioning - turned off to the bank. So everyone sweats. And Sheldon talks with the confidence of someone who knows what he's doing.

The atmosphere turns grim and you know Sonny's clock is ticking down.