The Rohirrim are the horsemen of Rohan in J. R. R. Tolkien's Middle-earth, brought to screen in Peter Jackson's The Lord of the Rings: The Two Towers from 2002. Their dawn arrival at Helm's Deep, led by Gandalf and Éomer to aid King Théoden, became one of the trilogy's most quoted turning points. Clips of the horn and charge music spread through edits, gaming videos and memes as shorthand for last-minute reinforcements, which is why the sound still signals a rescue arriving against the odds.