The CBS action-packed series has been on air since 2017 and it was in the first season that eagle-eyed fans spotted the glaring error. SWAT follows the lives of elite police officers who work to protect their city and it was fan favourite Hondo (played by Shemar Moore) who made the huge mistake.
Back in season one, fans were introduced to Hondo as Sergeant Daniel Harrelson.
He was a police officer who recruited members of the S.W.A.T team for the Los Angeles Police Department.
One of his main roles was the lead his highly skilled team on missions in the community he grew up in.
It was during an important task that Hondo made glaring mistakes that a viewer spotted.
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From season one, the episode titled Seizure saw Hondo lead his team on a mission at a maximum-security prison.
The intense episode saw the SWAT team be deployed to ease tensions during the hostage rescue mission.
The inmates of Helmsing Prison had formed three rival gangs and decided to spark a riot to seize control of the penitentiary.
Thankfully for the guards, the SWAT team were able to devise a successful plan and gained control of the jail.
It was during this phone call that the error was spotted, taking to moviemistakes.com, the viewer exposed the blunder.
They commented: “When Jessica calls Hondo to let him know about Deacon’s wife, you see Hondo answer the phone normally.
“Right after she tells him what’s up, you can see him holding the phone upside down, with the camera lens towards the bottom,” the fan added.
This mistake was a huge one as it was clear that during that moment production had reached the end of their take and no one had ensured that there weren’t any continuity errors.