There's a fight move in film and TV where one person uses both hands, usually as fists, to strike both sides of their opponent's head simultaneously. This is almost always portrayed as a special move, the fight scene slowing to an exaggerated swing of both arms and the opponent barely reacting. The most famous example is probably from a brawl in the 2009 film Sherlock Holmes showing off the detective's conscious planning and narration of his fights; the move occurs when he says "discombobulate."
I get that choreographed fights are full of flashy impractical moves, but I don't get why this one shows up so often. Does it have a name? What is it supposed to accomplish compared to a slap or a right hook to the same part of the face?