Arthur Penhaligon's Magical Adventures Continue As He Faces A New Grave Danger -- In The Form Of An Enemy Named Grim Tuesday. More Amazing Fantasy From Best-selling Author Garth Nix. Arthur Doesn't Think He Will Ever Have To Return To The Strange House That Nearly Killed Him On Monday -- The House That Contains An Entire World. But Tuesday Brings New Challenges -- In The Form Of An Enemy Named Grim Tuesday, Who Threatens The Well-being Of Both Arthur's Family And His World. Arthur Must Retrieve The Second Key From Grim Tuesday In Order To Save Everything -- An Adventure That Will Include Stealing A Sunship, Surviving A Very Weird Work Camp, Befriending A Bearlike Spirit, Fighting The Voidlike Nithlings, And Traveling To The Scary Far Reaches For The Ultimate Showdown.