I've just started writing a novel about a girl who lives in a small village. It is set in early 18th century England. The girl - my protagonist I suppose you could say - is being goaded by her widowed mother to marry a rich man. A mysterious young man arrives to claim his recently deceased father's inheritance and estate. The story will center around my protagonist falling in love with him and the mystery surrounding his arrival and sketchy past. Now, the problem I'm having concerning the plot is, well, the young man is actually a young woman in disguise. Shocking, I know! So far, I've only just introduced "him" so I'm not concerned really about how I'm going to write the reveal... but I am concerned as to whether I should throw some hints at the reader or just utterly shock them when the big reveal arrives. There is also the prospect of letting the reader know from the very beginning, so that it's just the narrator and reader's little secret. I know that's in a lot of other books, but it's not near as delicious as shocking them all at once... So what should I do? Help me please!