Tonight's blockbuster battle of the Hogwarts houses sees the wise and witty Ravenclaws go up against the proud and Ambitious Slytherins in a test of wizarding world knowledge. Only one team can claim an automatic place in the Grand Final. As always tonight's match up will take place under the watchful eye of the master of ceremonies Dame Helen Mirren. With Guest appearances and classic Potter movie moments this is another historic night in Hogwarts history.