Deadwater Fell viewers spotted a 'ridiculous' CPR blunder in tonight's series opener.
The brand new Channel 4 drama got off to a heartbreaking starts when a devastating fire ripped through a family's house.
Former Doctor Who star David Tennant was starring as Dr Tom Kendrick - a father who loses everything when his wife and children are killed in a horrific blaze.
Tom managed to escape but was the only survivor of a fire that killed his entire family.
After being laid on the ground outside the burning building, friend Mark started to pump Tom's rib cage.
Mark started to compress Tom's chest as he desperately tried to bring him back to life.
A fire engine arrived and the officers rushed onto the scene as flames slowly consumed the house.
But viewers were distracted by the manner in which Mark was conducting CPR.
Deadwater Fell viewers took to Twitter after watching the CPR scene.
One viewer said: "Ridiculous representations CPR on #DeadwaterFell"
"THAT IS THE WORST CPR I HAVE EVER SEEN, "added another.
A third said: "That CPR couldn't burst a bubble"
"Despite absolutely the worst CPR anyone has ever seen I'm already hooked on this #DeadwaterFell," said a fourth.
When the drama continues next week, Tom immediately becomes the prime suspect in the deaths.
While the Channel 4 drama is fictional, it bears eerie echoes to a real life murder that is the focus of a Netflix documentary.
Deadwater Fell's creators have confessed they were heavily influenced by true crime documentaries - and in particular The Staircase.
*Deadwater Fell airs on Fridays on Channel 4 at 9pm
