While walking around his neighbourhood, Abdul Razak Abd Majid chanced upon a key pouch, which held a Toyota car key, on a bench.
Instead of handing it over to the police, he, his brother and their friend decided to look for the car to go for a joyride.
Yesterday, Abdul Razak, 41, was jailed for six months, while his sibling, Muhammad Jeffri Abd Majid, 30, was jailed for eight months after pleading guilty to car theft. They were also disqualified from driving all classes of vehicles for a year.
The case involving their friend, Mohammad Noh Fandi Kamis, 22, is still pending.
Abdul Razak found the key pouch on the ground floor of Block 61C, Strathmore Avenue, near Commonwealth Avenue, at around 11.30pm on March 3.
He took it home and showed it to Jeffri and Noh Fandi.
Deputy Public Prosecutor (DPP) Du Xuan said Noh Fandi then came up with the plan to look for the car so they can use it to drive to the Arab Street area to look for a friend.The brothers agreed to join him.
The unemployed trio then went around their neighbourhood in search of the car.
Noh Fandi tried to unlock Toyota cars at random by pressing the "unlock" button on the key, while the brothers acted as lookouts.
They finally found the correct car at a multi-storey carpark near Block 61, Strathmore Avenue, at around 12.10am on March 4.
After unlocking the $90,000 Toyota Camry, the trio got in and drove off.
However, an eyewitness saw them behaving suspiciously at the carpark and alerted the police after noting down the vehicle's registration number.
Officers who arrived at the scene met the car owner, who confirmed that his vehicle was missing. His wife was the last person to drive the car and had parked it about two hours before Abdul Razak found the key.
Officers arrested the trio and recovered the car at Sultan Gate, off Beach Road.
DPP Du said: "The victim's car was found to have sustained scratches and dents on the left and right sides... The car was repaired and the cost of repair amounted to $642. No restitution was made to the victim."
For stealing the car, each of the two could have been jailed for up to seven years and fined.