 How would you describe the changes in tone through the passage?
This walk was part of a regular routine of physical exercise that kept his body hard and resilient in spite of long hours spent in the laboratory. All I want is to get out of here—" "Gotcha, chief," Brent whispered understandingly. Swift shadows moved expertly before his astonished gaze. Another guard was caught and silenced as he came around the end of the corridor. The electric eye tripped a screaming alarm, but the broken key in Brian's hands opened the complicated lock in a matter of seconds. The sharp, ripping blast of an atomite bomb thundered along the street and slammed them to the ground.
 From detached to intense
 From detached to intense  From excited to calm  From scary to tranquil  From calm to depressing