Sure enough, all those trailers and cones were for a movie. There were huge lights set up just across the street from me at one of the hospitals that dot my street.
I spoke with one of the security people (that kept all of us onlookers far away), and she said it was for a French movie that sounded something like "Fonzie." (I certainly wasn't going to ask her to spell it!)
And I was right about the catering truck. They were carrying gorgeous salads out of the truck and serving them to the waiting hordes dining in tents set up on an empty lot. There were lots of people milling about and I was feeling a little paparazzi-ish, so I just took a picture of the truck.
Now I just have to look out for a French movie about Fonzie!