Even if, like me, you have seen Dame Edna: The Royal Tour before, you should catch it again during these final weeks. Both the stuff you have seen and the considerable new stuff each improvisatory performance necessarily yields will have you in the same stitches. And if, unaccountably, you have abstained so far, rush to make amends. Barry Humphries will make you laugh throughout, and again in later life, whenever you recollect him in laugh-punctured tranquillity, which will be often. And now you also get as a bonus Cady Huffman as one of the Gorgeous Ednaettes, who not only fully lives up to the designation but also, through expressions and gestures, makes a role out of what is merely meant as decoration.