This episode takes a closer look at the late years of Impressionism, using the last show these artists did together as a starting point. Waldemar looks in considerable depth at the work of Georges Seurat, taking into consideration his academic training at the Beaux-Arts School in Paris and the artists that influenced him, such as Piero della Francesca and Puvis de Chavannes. There is also an insight into the complex but fascinating world of optics and art, and the ways in which the Impressionists were using the new discoveries in light and eyesight to influence their work. A fascinating 'after-image' experiment brings to life the ways in which our own eyes see colour, both in its presence and its absence. Van Gogh's time in Paris, a period very little is known about, is also covered, charting the incredible journey the artist made from his brown and dull canvases to the splendid colour and light that pervaded his work on the cusp of his departure for the South of France. The film finishes with a revisiting of Monet and his later waterlily paintings in the Orangerie in Paris. Waldemar investigates how a bad case of cataracts was responsible for a seismic shift in his colour palette and his brushstrokes. Spending time with an ophthalmologist, he finds out how old age and a fairly common ailment of the eyes caused Impressionism to shift and become radical again at the turn of the century and into the 20th century.

• Susan Doyon

• Waldemar Januszczak