A woman has described the “surreal moment” she recognised her grandfather in Peter Jackson’s They Shall Not Grow Old film – after spotting his nose in the footage.

Jenny Pateman from Canvey couldn’t believe her eyes when she saw Thomas Frayne marching in the First World War documentary.

Jenny had only known her grandfather as an elderly man, but she rewound the footage and paused it to double-check – stating there was no mistaking him.

The feature length film is based off archived footage from the Imperial War Museum – used to depict life in the trenches.

Many of the clips have been slowed down and put into colour by the highly regarded Lord of the Rings director.

Mr Jackson previously stated he embarked on the project in the hope of helping the descendants of those who fought in the war understand the hardships that came with the battle.

But Mrs Pateman, 55, spotted her grandfather in footage that had not been slowed down and was still black and white.

She was just eight years old when her grandfather died at the age of 77.

She said: “I was gobsmacked. It brought tears to my eyes, seeing him as a young man and walking along.

“He got gassed at the Somme and never fully recovered. I only ever knew him as a man in bed.”

But Mrs Patemen said she knew it was him when she spied a ‘distinctive nose’ that she had seen in photographs, adding that her brother is the spitting image of him.

Mr Frayne joined the King’s Own Yorkshire Light Infantry in 1915 before attaining the rank of corporal and joining the Machine Gun Corps.

He earned the Military Medal in 1916 when he showed “great coolness and devotion to duty” fetching ammunition under a “heavy enemy barrage”.

He became a sergeant in the York and Lancaster Regiment, where he also progressed to 2nd lieutenant.

Mrs Pateman was so moved by the ‘harrowing’ colourised footage of bloodied corpses in the trenches that she stopped watching.

She said that the black and white clips she had been used to looked historical, but the immediacy of the colour footage disturbed her.