This video explores the grammatical history and validity of the "singular they" pronoun. It begins by acknowledging the recent adoption of the term by major style guides like The Washington Post and The Economist, contrasting this with traditional grammar rules that often penalized its use. The narrator explains that while "they" is traditionally a plural third-person pronoun, its use as a singular pronoun for indefinite antecedents (like "anyone" or "a journalist") has a long history in the English language.