When Deputy Commissioner George Sanders, Jack's ex-father-in-law, is implicated in a murder of a prostitute, Jack becomes determined to clear his name. He also has to deal with the reappearance of his ex-wife Rosie. Meanwhile, Phryne tries to perfect her fan dance, so she can go undercover at a gentleman's club run by Madam Lyon.

Inspired by a Kerry Greenwood short story and set amidst the passion and fanaticism of 1929 Australian Rules Football. When Phryne is duped into investigating the coach's missing 'lucky cap', she discovers a gruesome murder instead - the local team Captain is found hanging by a rival team's scarf and it seems at first a clear - cut case of murderous sabotage.

Now estranged, Phryne and Jack step around each other to investigate a murder and the disappearance of a valuable manuscript.