I have a suggestion for the topic for this month's Challenge. I call it 'Time-Warp'. It's where someone from one time somehow gets transported to another time. Maybe someone from the far past appears in today's world. Or someone from today's world get transported either to the past or the future.
As an example, here is a young woman who was sunbathing topless on a beach today, and suddenly she appears in the family room of a house in the Victorian era...