Lovejoy invites a suspicious Charlotte away for a weekend, but their trip to Wales turns out to be a hunt for a murderer.

When Charlotte asks Lovejoy to help her value the contents of a private nursing home it seems straightforward enough - until there is an attempt on Lovejoy's life.

Lovejoy finds an unusual and valuable Chinese cannon being used as a plant pot, but when Charlotte takes him to London to sell it they are kidnapped.