I will leave you with a scene from the so-so disaster/horror film THE HAPPENING, which I watched last night and which I have posted about earlier today without finding the specific scene I wanted to show as way of illustration.
Forgive the re posting but I must admit my film critic's eye (?!) found it fascinating!
The film by M. Night Shyamalan (A bollocks name btw!) tells the story of how the earth's plants suddenly emit a toxin that forces the general population commit mass suicide ( like you do!)........yes....a real load of crud if ever I saw it... but one particular scene where construction workers literally walk off their tall building, lingers long in the mind, and perhaps stands as an interesting example of just how talented Shyamalan could be given the right story...
I think it is a chilling little piece of cinema.