Bow Ties Uk In The Uk If Asked To Wear "black Tie" For A Wedding What Can I Wear ?

In the uk if asked to wear "black tie" for a wedding what can i wear ? - bow ties uk

I thought about using a black shirt, black dress of dinner and do not know whether to continue to speak the word of the invitation and lead to black fly?
or should I whitefly with a black T-shirt? (or red?)
must be a fancy shirt-front, or I can go with a normal?