In 2012, when the BBC’s Sherlock was all the rage and people were freaking out about the new season, a Sri Lankan Twitter mutual committed a cardinal internet sin. In a series of gushy tweets about the season’s first, long-awaited episode barely an hour after its release, this person — without meaning to, I’m sure — revealed a major plot point. It was a weekday afternoon, and very few had watched it. Naturally, everybody lost their shit.