Jack Potsby was an unemployed man whose only redeeming feature was his appearance. He was found murdered in his studio flat, apparently part of a burglary.
Potsby was a typical loser who had a severe gambling habit. He had lost much of his savings because of his habit but one day, luck was on his side and won a huge amount of money. Around that time, Goldie Potsby-Mahn entered his life and the two married. Out of love, Potsby decided to have life insurance using his winnings but because of his habit of spending money quickly, Potsby-Mahn was worried the debt he would rack up would be at least as much as the insurance.
Around a year later, Potsby-Mahn decided to kill him before he started to spend any money. She created a knife made of ice using a mould from a scrap of paper and stabbed him in the back. To make the attack appear to be the result of burglary, she smashed the window from the outside. She quickly cleaned the weapon, got rid of the knife using her cooking pot cooking pasta and fooled Chase M. Downes into catching Buster Nicks the burglar, who coincidentally was planning to break into a ground-level flat.
However, Nicks's statement created inconsistencies with Potsby-Mahn's story and ultimately exposed her as Potsby's killer.
- His name contains the word "jackpot", referring to the huge sum of money he won.