What is significant about the many scenes showing low ceilings just above the heads of the characters in the movie And Then There Were None?
In novels such as And Then There Were None by Agatha Christie, the author drew heavily on her childhood and adult experiences of the environment she grew up in, or vacationed in. These settings characteristically wove themselves into the sets and backgrounds for many of her works. For example, she spent a lot of time in the West Country of England and loved the landscape there - it is olde worlde and cottagey and there are very many tiny, quaint cottages and houses. These still have many low doorways and ceilings - either due to floor/garden height raising over the centuries or being built for residents much tinier than we are today. So, we 'modern giants' have to stoop. Also adds a gothic-esque charm.
Spatial imagery is one of the basic elements of imagery, along with visual, auditory. olfactory, and tactility that helps reveal themes of stories. The spatial imagery converts the local, physical environment of the story into a metaphor for either a character's struggle against some opposing force, or to demonstrate how far a character has grown, physically and or emotionally. The imagery is especially revealing as a motif in particular, to help the reader understand the story to a greater degree. Low ceilings and high floors often are used with characters who have to overcome great obstacles.