This is the third book in the Eye Spy series about Alex and Donna Macintyre and their detective service, Eye Spy Investigations.
Alex is afraid of snakes, so when his sister Donna befriends Jake, an Australian boy with a pet snake called Queenie, he isn't happy. Jake is staying with the O'Connor family at Acacia Villa, once the home of Victorian artist, Gabriel Pascoe. When the artist's great grandson, Fred Pascoe, tells the twins how Gabriel Pascoe's most famous painting, Lady in Red, went missing seventy years ago, they volunteer to try and find out what happened to it.
While their father, an inventor, is preparing for the official launch of his most successful invention, a search and rescue robot, Alex and Donna pursue their search for the missing masterpiece. Then Acacia Villa itself is threatened with demolition. It looks as if their new friends will lose their home, and Holcombe Bay will lose an important historic building. They suspect that Mr Mortimer, the man who wants to demolish Acacia Villa, may know the true location of Lady in Red. But he is a friend of the twins' mother, and the godfather of their baby half-sister, Sophie. Criticising him could open up family rifts, which have only recently healed.
Then Queenie the snake goes missing, and a train of events is set in motion which leads the twins and their new friends into terrible danger. Help comes from an unexpected quarter, but will it arrive too late? Can Alex overcome his fear of snakes? And will the twins ever be able to return Lady in Red to its rightful owner?