Half-Life, Valve's influential first-person shooter first released in 1998, built much of its tension from sparse dialogue, environmental audio and moments when characters reacted to sounds they could not see. Short lines lifted from the game have long circulated on soundboards, where players collect and replay brief moments outside the original levels. This particular question works because it is open-ended, so editors can reuse it for almost any suspicious noise, and its game association gives an instant, knowing cue to viewers who recognise the series.