grip

A grip is the crewmember responsible for setting up dolly tracks and camera cranes, erecting scaffolding, moving props or scenery, or the adjustment or maintenance of any other production equipment on the set. A physically demanding job. The "key grip" is the head grip that coordinates all of the other grips in the crew and receives direction from the gaffer or head lighting technician. The key grip's right-hand assistant is known as the "best boy grip."