They really did....*Contains Spoilers*

They really did go to Paris during the filming of the two-parter of Castle. I'm sure everybody was curious about that and so I asked the girl herself on twitter (Molly Quinn = Alexis) if they really did and here's her response.

Also, was super excited to get a reply from her! Besides Castle himself, Alexis is my favorite so to get a reply from her was awesome!