It was Sunday, the toughest puzzle of the week, so I didn't feel bad about springing 5-Across on you. The clue was [Bolt that's like lightning] for a five-letter word. Turned out to not be weather-related at all, though -- the answer was USAIN, as in Jamaican super-sprinter USAIN Bolt, who's indeed lightning-like on the track.

Welcome to one of the most devious clue types in the crossword writer's arsenal: the masked capital letter. You take a proper noun that also happens to be a standard, non-capitalized English word, and hide it at the first word of the clue. This "masks" that word's status as a proper noun, since the solver assumes that it's capitalized since it's the first letter of the first word in the clue. Sneaky!

Try this one: [Ally in court] in six letters, starting with M. Got it? It's not an "ally" as in a teammate, but rather "Ally" as a name, which might lead you to the correct answer: MCBEAL, as in TV lawyer Ally McBeal.

Some celebrities' names have been used so often as masked capitals that they don't surprise solvers much anymore. After you've seen [Cruise around Hollywood] for TOM a few times it ceases to be tricky.

It's not just people: cities can also get in on the fun. [Nice friend] or [Nice king] is going to be about the French city of Nice, yielding the common crossword answers AMI and ROI. Note that masked capital letters don't work for songs, movies, or TV shows, since those would need to be in italics or quotes, which gives away the game..

Speaking of games: one last source of sneaky masked capitals is sports teams. [Magic place] is going to be ORLANDO a lot of the time, referring to the NBA team, and [Sharks play there] will lead you to SANJOSE, referencing the NHL team.

Have you unmasked a masked capital letter lately? Tweet it to #beastxword so none of us will get fooled again!

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