Cillian,
I really like the
Small world: Alien-landing scenarios in a small village.
since this is a science fiction staple. You could show movie posters of alien landings that are both gentle or slightly more scary.
Here is a list of the nice ones: https://www.sciencefocus.com/space/friendly-alien-invasion-films
although, Close Encounters scared the beejeebers out of me when it came out ( I was 11!), when the toddler was taken.
and ones with a more child friendly vibe: