Britannia engine starting
An understandable reaction to being asked to hold a prop.
An incident at LGW in the 70's resulted in the guy holding the prop getting hit by the blade that was in the 3 o'clock position when it arrived at where he was still standing. The reason he was still there was that the engine started but the blades didn't move as the rear turbine blades were stuck on the turbine shroud, which is driven by the propeller shaft. He pushed, it freed but he was hit by the next blade.
Fortunately he survived but all were wiser to the power of the propellor.