 His next project, "Gunpowder, Treason and Plot" (2004)"," was a four part mini-series for the BBC on the lives of Mary Queen of Scots and her son James VI of Scotland/James I of England.Lewis portrayed historical figure John Knox, a prominent leader of the Scottish Reformation who supervised the preparation of the Reformed Church of Scotland's constitution and liturgy.The BBC and The Discovery Channel partnered in 2005 to produce a made-for-TV film, "Supervolcano", that proposed a scenario where the magma chamber beneath Yellowstone National Park erupted.