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Matthew: "This looks like the outer circle from Dante's Inferno!"
Rosamund: "The outer circle?!"
— Matthew Crawley and Lady Rosamund Painswick upon first entering the Blue Dragon.[src]

The Blue Dragon is a jazz club on Greek Street in the Soho area of London where Lady Edith Crawley, Matthew Crawley, and Lady Rosamund Painswick go to find Lady Rose MacClare after being told by a taxi driver that he had taken her there. They found her there dancing wildly with and kissing Terence Margadale, and took her away soon afterwards.