Three Jolly Luck
From Discworld & Terry Pratchett Wiki
The Three Jolly Luck Takeaway Fish Bar was not one of Ankh-Morpork's most successful businesses, nor among the longest-established. In fact, it didn't last through its grand opening. It remains famous as an example and warning of the necessity, in Ankh-Morpork, of getting not only one's ducks in a row before beginning any enterprise, but one's rocs and phoenixes as well. (1)
An Agatean gentleman remembered only as Mr Hong chose to set up the shop on the site of a former fish-god temple in Dagon Street and opened on the night of a full moon and a lunar eclipse at the winter solistice. Reports of what happened then are as varied and contradictory as usual from a crowd of Morporkian witnesses (2), but certainly the shop disappeared, or most of it, along with Mr Hong, or most of him. As nearly as could be determined, he left behind one kidney and half an earhole.
The Patrician's family motto suggests letting well enough alone, but he takes a close and wary interest in new projects. Sometimes he cites Mr. Hong to explain his caution.
For the connection between a fish shop and Dagon street, see the annotation there.