Was that the one where Meg became obsessed with Brian?
No, it was when Meg, because everyone is so horrible to her all the time, became obsessed with an extremely conservative form of Christianity, and it allowed good ol Seth MacFarlane to make all sorts of sweeping anti-religion statements. I didn't care for that, but if it had been funny, I would have overlooked a lot - Douglas Adams, for example, was frequently anti-religion but he was funny about it. But it wasn't funny. At all. As usual on Family Guy these days, I spent most of the episode feeling sorry for poor Meg and wanting to give her a hug.
The funny parts involved Stewie kidnapping the TNG crew. Some of that was pretty funny.