It happened around 2:30am in an industrial business strip center parking lot off S. Sam Houston Parkway near W. Bellfort.
According to investigators, the victim and some friends had just left a party at Million Pavilion party hall rental facility after getting into a verbal argument.
They were driving south on the S. Sam Houston Parkway feeder road from U.S. 59 when the driver says he heard a loud pop and then heard his back driver's side window break.
He looked back and saw his friend had been shot, so he pulled into the parking lot and called 9-1-1.
The victim was pronounced dead at the scene.
The driver did not see the shooter's vehicle, but passers-by in other cars saw what happened and pulled over to help.
Those witnesses told police there was a black Buick Regal that drove by and fired the shot.
Police are trying to figure out if this was a targeted attack from another party attendee who was involved in the verbal altercation at the rental hall, or if it was a random drive-by shooting.
Anyone with information is urged to call Crime Stoppers at 713-222-TIPS. All tipsters remain anonymous.