Vigil fans were stunned as Amy Silva’s life was put in danger as she edged closer to revealing the identity of a spy on board the submarine.
The thriller saw the detective (Suranne Jones) continuing her difficult quest to find out who killed Chief Petty Officer Craig Burke (Martin Compston) on board a Trident nuclear submarine.
Silva suspected the gas that killed chef Jackie Hamilton could also be responsible for the death of Burke – but Captain Newsome (Paterson Joseph) was more concerned with it flooding the missile compartment and leaving Britain vulnerable to nuclear attack.
Back on dry land, Kirsten made an astonishing discovery, finding evidence that Ben Oakley had supplied a photo to Russian spy Peter Ingles which led to the death of Jade Antoniak – a peace campaigner who was in a relationship with Burke.
Silva and Glover (Shaun Evans) donned hazmat suits to search for evidence in the contaminated section of the submarine around Jackie’s body, discovering a note that suggested someone else on board was involved in the conspiracy.
As they made their way to safety Glover began to feel unwell – and they realised his suit had been slit open on one side, exposing him to the nerve agent.
But more danger was lurking for Silva, who found herself being bundled into a torpedo tube which was rapidly filling up with water.
It was the stuff of nightmares for many viewers on Twitter.
@_mouldy_ wrote: “Hope everyone enjoys their nightmares about being trapped in a torpedo tube filling with water.”
Bella said: “Dying in a torpedo tube has shot up to the top of my ways I would rather not die list.”
waxedpaperdoor posted: “Didn’t know being trapped inside a torpedo tube on a submarine was a thing I was afraid of, but I AM NOW, THANKS.”
And tillygolightly said: “I’m going to have nightmares thinking about how in a torpedo tube no one can hear you scream.”
Will Amy survive? Viewers will have to wait until next Sunday at 9pm to find out.
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