Agents of history. Partners in Mystery. Sisters in solving crime. Twelve-year-olds Lizzie Sancho and Dido Belle are from different worlds - Lizzie lives in Westminster in her dada’s tea shop, while Belle is an heiress being brought up by her aunt and uncle at grand Kenwood House - but they both share a love of solving mysteries. And after saving Lizzie’s father from attempted murder surely there is no threat too challenging for this detective duo?

It’s the summer of 1777, the night of the grand unveiling of the Sancho-Mansfields family portrait and a celebration of friendship, family, and freedom! But all too soon things take a dark turn - the painting has been stolen! Now it is time for Lizzie and Belle to put their sleuthing skills to the ultimate test, following a trail of thefts, kidnappings and even poisonings that haunts the twisting London streets. With a grand conspiracy afoot, and a mysterious organisation threatening their closest friends and family, who can Lizzie and Belle trust? Once again it is up to the two girls to unveil the truth and put an end to the villainy that plagues the city.

- Browns Books Synopsis