I highly recommend A Very English Scandal. Both Ben Wishaw and Hugh Grant are excellent. (spoils)
Being based on a true story can it be called a black comedy? Well, there's certainly a comedy of errors element in it. It's a love story, too. It's gay history. It can also be taken as a statement against national ID cards. I nearly cried at the very end when they did a "where are they now" bit because...well, I don't want to spoil that. And it has Eve Myles playing a character named Gwen who had a line that made me laugh so hard it brought tears to my eyes, it was so unexpected, yet so heartfelt. Poor Gwen. And poor Bunny.