What feels strange about the figures in Seurat's 'Bathers at Asnières'?

The French artist Georges Seurat painted 'Bathers at Asnières' in 1884 when he was just 24 years old. It was the first painting he exhibited in public.

It’s a simple picture of men and boys relaxing by the River Seine and yet there is something unsettling about this scene. The people seem both present and absent - there and not there.

Emmelyn Butterfield-Rosen explores Seurat's figures to explain how, by painting them in this way, he undid centuries-old beliefs about how people should appear in art.