There was likely crime committed on Noah's ark. Stuff happens every day all over the world.

>> But I just read of a crime that happened in Covent garden.<<

Have you ever heard of any neighborhood in any city that a crime has not occurred?.

Before you get set on a plan -- check how you will travel back and forth. You are doing this very last minute and flights and Eurostar fares may be really high -- or you may have a hard time finding seats /schedules that work for you.

OMGosh, is there anyplace in the world where a crime hasn't happened in recent days/hours?

Instead of focusing on the negatives, why not focus on planning a nice trip? I still think it's a bit crazy to try to make a worthwhile trip to Annecy or Paris in the time you've got, but if it doesn't bother you to spend hours of a very short trip in airports or train stations, go for it. It would greatly diminish the experience for me (and I spend loads of time in European train stations and airports - it's hardly the best aspect of any trip I take).

It's La Fête Nationale, or Le Quatorze juillet, not Bastille Day.

I really do not care if Anglophones call it Bastille Day. No big deal.

Clearly, Paris is your only reasonable option, probably by Eurostar (but book it immediately to save a little money!). During a future trip, you and your daughter will be able to plan a more reasonable excursion to Europe. You can even take a quick trip out of the city if you feel impelled to see something else. For example, Reims is only 45 minutes from Paris by TGV.

I have to put things down on paper to see if they work:
July 10 leave NYC
11 arrive London, fly to Paris, tour Paris sleepily
12 Paris
13 Paris
14 Paris, evening train to London
15 London
16 London
17 London, fly home

You'll get two full days and two partial days in Paris. You'll get 2 full days and a partial day in London. I'd say that is a bit quick, but still sounds like an awesome trip. I'm not not one to want to sit in a city for an entire week. It all depends on how you like to travel. But DON'T let people here tell you this can't work. It definitely can if you go into this understanding the true time you have in each place and you're OK with it. Trust me...we've seen proposed itineraries much worse than this.

>>You'll get 2 full days and a partial day in London. <<

Two days -- no 'partial day' because seldom can anything be done on departure day . . . unless you mean the partial day is the few late evening hours after the train from Paris.

>>I'm not not one to want to sit in a city for an entire week.<<

Well - if all one does is 'sit' I can understand that. >)

Ihope2travel: London is the largest city in western Europe by a LARGE margin with more things of interest than one can imagine. If two days is all you have -- then pick your 4 or maybe 5 main 'must-see's' and leave it at that.

I’m thinking we would pick Paris or Annecy

Paris! It is a lot easier (takes way less time) to get to Paris than to get yourselves to Annecy (which I think it a nice add-on for trips but only if you have a few days to spare, which you do not). I think you have time for Paris. I don't think you have time for Annecy (what do you want to see there in particular anyway? What's the draw?).