Jumbo East Frisian melody

Rupert and the annoying mother-in-law. It was one of those afternoons with strawberry cake and whipped cream, a wonderfully blue sky and a balmy breeze that couldn't have been more beautiful. If it hadn't been for Rupert's annoying mother-in-law, who invited herself round for coffee. The bang was quickly explained: out of the blue, a seagull had dropped a piece of debris that definitely didn't belong on Rupert's windscreen - a human finger. And Rupert's neighbour, an annoying music teacher, had had his porch door open for some time. When Rupert approached the house, he suspected the worst. And sure enough, the teacher was lying dead next to the piano. A case for super detective Rupert, and for his mother-in-law, who refuses to be shaken off.