The 2001 epic 'The Lord of the Rings: The Fellowship of the Ring' features the legendary confrontation between Gandalf, played by Ian McKellen, and the ancient Balrog. As the Fellowship flees the Mines of Moria, Gandalf chooses to stand his ground on the narrow Bridge of Khazad-dûm. He famously strikes his staff into the ground and shouts, 'You shall not pass!' which leads to the bridge's collapse. The scene ends with the Balrog falling into the chasm, dragging Gandalf down with it in a moment of tragic heroism. This clip has become a pillar of meme culture, used to represent ultimate defiance and gatekeeping. It is frequently applied to situations where a single person or thing prevents a total disaster or stops progress. Users often use it to represent security software, strict teachers, or stubborn pets blocking a doorway. Example captions include 'Me at 3 AM defending the fridge from my own self-control' and 'The one loose screw holding my life together.'