The Night Watch by Rembrandt has perplexed scholars for centuries with its array of hidden clues and coded messages. Peter Greenaway uses his new film, Nightwatching, to claim that the artist used the painting to expose a murderous conspiracy amongst Amsterdam's ruling classes.

Completed in 1642, The Night Watch was commissioned by local militiamen who wished to be immortalised on canvas. Rembrandt was then one of Europe's most celebrated artists.

According to Greenaway's film, the artist discovered that the militia captain had been murdered and his colleagues made his death look like a training ground accident.

The Night Watch contains this hidden message and also mocks the militiamen, insinuating that one is gay and another is a womaniser, Greenaway believes.