When looking in Frankie's scrapyard for a replacement back indicator lamp for his pickup truck, Lovejoy is persuaded to buy a rusty old cannon, too.

After a ram-raid smashes his Sheraton desk, Lovejoy has to look for new stock; he also becomes a hospital visitor.

Jim Leonard, Lovejoy's mentor, sets up a country house weekend for an elaborate con. Lovejoy involves Eric, Tinker and Jane, but finds out too late that he is also a victim.