'We knew we had to solve the mystery somehow!' The world of Kalu, Malu, Bulu and Tulu is always buzzing with mysteries, big and small. And that works just fine, because the four young 'detectives' are raring to solve them. Wherever the four clever friends happen to be-at their school hostel, next door at the Zamindar Mansion, or away on holiday in Mandu or Cherrapunji-they have a way of smelling out a mystery and keeping their nerve in the face of daunting dangers and terrifying threats to find what lies at the bottom of it. Join the Lu Quartet on their adventures in caves and ravines, secret chambers and dark mango groves, and see if you can unravel the twists and turns of the whodunits just as they do.These thirteen classic stories by Nalini Das originally appeared in the reputed Bengali magazine Sandesh and have been translated for the first time into English by leading children's writer Swapna Dutta.