Leslie ran to catch the bus.
In the course of running, her shoe stuck to wad of gum on the sidewalk.
This caused her to twist out of said shoe in such a manner that she fell off the curb.
In the course of falling, she saw a series of bright lights.
Head smacked pavement.
When she next opened her eyes, the people were gone but the city remained.
Leslie assumed she was in purgatory, but couldn’t think of good deeds to do with nobody around to do them to.
So she lived in an Aldi until aliens got her.