One NCIS viewer has spotted a major blunder in a murder investigation scene after re-watching season four of the CBS drama. The fan took to an online forum to share their findings.

An observant NCIS fan has pointed out a glaring error in a murder investigation, sharing the plot hole on a CBS show forum.

The viewer noticed a crucial piece of evidence changing from one scene to another while re-watching season four, episode four. The NCIS episode, ‘Faking It’, saw the team investigating a naval officer’s death. A routine traffic stop turned deadly when the officer’s body fell out of a vehicle.

Initially, two police officers pulled over a driver for speeding. The driver apologized, saying his pregnant wife had called him while driving.

Upon noticing the man’s pistol, the officers demanded he exit the vehicle slowly. Lou Giotti (played by Nolan North) inspected the gun and found it had recently been fired.

Suddenly, a car crashed into the police car, and the driver was later found dead with a gunshot wound and heavy bleeding. In a chilling twist, “NCIS” was written in blood next to him, reports the Express.

Later, Timothy McGee (Sean Murray) found a blood-smeared phone in the car. However, one fan noticed a significant error with this evidence, stating: “The mobile that McGee finds in the car changes design between shots.”

“There is a black section in one shot and not in others. The blood also changes.”

In the initial scene, a phone with a tiny blood smear on one of its buttons is found in the car. When Timothy scrutinizes the evidence, the phone model has changed and there are multiple blood stains.

However, Tony DiNozzo (Michael Weatherly) didn’t notice the error. In other news, NCIS’ Ducky (David McCallum) has shed light on why Ziva David star Cote de Pablo left the show in season 11.

In a 2016 Reddit thread titled “I’m David McCallum. I play Ducky on the hit TV show NCIS and my debut mystery novel, ‘Once a Crooked Man’, hits shelves next week. AMA! (Ask me anything),” a fan asked why Cote De Pablo left NCIS. The actor honestly replied: “At the time I was astonished when Cote left.”

“But in retrospect, it seems that she was not up to handling the demands that the character put upon her.”

Cote did eventually return to her role six seasons after her departure.