In some of the editing programs like Sony Vegas Video there is such a preset,but in AE is missing.For nice result check Andrew Kramer old film look tutorial.
For nice nuclear explosions you can use the Wondertouch application – Particle Illusion,it has not only great presets,but it’s not so hard to work with.
I guess that Trapcode Particular would do the job,for more info visit Trapcode.com for info about using the plugin you should check the download section of the site mentioned,of course here on the COW there’re plenty of tutorials for this plug-in.One of my favourites is Andrew Kramer’s
I’m sure that it will work,even if you shoot every person separtely and if you use the correct technique,no person would be able to find out how you got the result.