Apple bobbing
The brutal and sadistic imagery surrounding Joyce's untimely death in an apple-bobbing tub underscores the brutality of the murderer plaguing the town of Woodleigh Common. Not only that, the image of the floating, harmless, and playful apples is a powerful juxtaposition to the malevolent act of murder.
Pumpkins
Throughout the novel, Christie describes carved pumpkins with great detail. She talks about their orange skin and flickering lights, which in turn creates a strong visual image in readers' minds and creates a tense, scary atmosphere that is evocative of the Halloween setting.
Witches and Halloween costumes
The imagery of the witches and children in their oftentimes elaborate and evocative costumes during Halloween captures the excitement and festivity of the occasion.
Paganism
Naturally, because Halloween is a Pagan holiday, there is substantial imagery related to Paganism. For instance, there are countless images of pentacles, pentagrams, horned gods, all-seeing eyes, witches, warlocks, and other fantastical creatures. This imagery not only shows the setting of the novel; it underscores the complexity of the murders Poirot investigates.
