The philosopher Alexius Meinong argued that something can have characteristics even if it does not exist. The grey-eyed goddess Athena does not exist, but it is still true that her eyes are grey. She shares this lack of existence, for example, with round squares, which possess the characteristics of roundness and squareness. Meinong calls such peculiar things "homeless objects", as they do not fit easily into the existing categories of thought.

Meinong's insight is used here to pursue some filmic thought experiments. (Fortunately the medium of film is ideal for separating a thing's existence from its characteristics.) The film's main character, P, lacks characteristics entirely. This makes P useful in experiments where pain or suffering may be involved.

The film raises questions regarding our perceptions of reality. Does Sherlock Holmes play the violin, or does he not? Is the child correct in thinking that its hobby horse is more real than a real horse? We see only what we want to see: what are the consequences of this?

Concepts of reality employed in daily life are sophisticated and flexible. We know that fantasies, for example, are quite real in one sense, and that in another sense they are not. But this flexibility can also be used to prop up denials of realities we would rather not acknowledge. It conveniently permits us not to see homeless children on the street.