Goofs

Royal Navy helicopters are battleship grey. The helicopter is clearly an RAF Sea King with yellow paint scheme and bullseye (Roundel), but with the words Royal Navy added.

A civilian police DCI untrained in operating a nuclear submarine layouts would not be sent to investigate a death. The Royal Navy Police or Ministry of Defence Police would rather send its own detective.

The submarine's propeller is shown with a trail of bubbles. This is cavitation and causes noise (and potential propeller damage) and would be fatal for a supposedly stealthy submarine.

The Sea King is no longer in the active Search & Rescue role and the military truck on HMNB has been replaced by MAN trucks.

The Sea King helicopter used to ferry DCI Silva is yellow, so is an RAF aircraft. Royal Navy Sea Kings are grey, with SAR aircraft having bright red nose and tail sections.

All the Royal Navy personnel on HMS Vigil are wearing radiation monitors yet Amy Silva is not issued one while moving around near the reactor.

A number of uniform errors are evident. Royal Navy Officers' cap badges, for example, do not have the text "HMS Royal Navy" sewn into them. The flag worn on the upper arm of the crew's uniform is not the White Ensign that is worn on the working rig of sailors throughout the Royal Navy; rather, it is an adaptation of the Ensign that does not really exist.

The Long / Lat position given by the helicopter when waiting for the submarine to surface, is 75 N 001W. This is up between Greenland and Svalbard near the arctic circle. Perfect submarine territory, but well outside the range of a helicopter.

The head of the Royal Navy submarine service is now a Commodore, not Rear Admiral. This may be for dramatic overlook.

There are far too many Chief Petty Officers in this series. Burke for example should control a few Petty Officers and in return many Leading Hands and Able Rates. He alone should not have just detected the sinking trawler or even the other submarine.

Chief Petty Officer Craig Burke asks permission to put the sound he heard on the speaker. Submarines of all kinds generally run quiet to prevent detection. As a CPO and sonar operator, Buke should never have asked that and no such system should exist on a submarine. The Captain should have listened to in on headphones.

It is already depicted that DCI Silva suffers from flashbacks of a car crash that killed her husband and make her parents take custody of her daughter. She should have immediately reported her mental health or seek treatment or even DSU Robertson should have figured that out. She should not have continued as a detective, let alone sent underwater.

After the arrival on the submarine, a person on a loudspeaker (which should not exist on a submarine, since its supposed to operate quietly), mentions that the "Conning Tower" hatches are closed. Modern submarines do not have conning towers; the vertical extension of the hull with the top entrance is called a fin in the British Navy and a sail in the US Navy.

When Amy Silva came off the helicopter onto the submarine the chief petty officer replacing Craig Burke was clearly coming on second. When scene cuts. 4 people are on top of the submarine 2 dressed in yellow (current submarine crew) 2 dressed in black and red (Amy and new CPO) YET when one yellowed crew went down, then the character DC Amy (before new CPO climbed down the ladders) the camera pans up showing the 2nd yellow submariner shutting the hatch yet the new CPO hadn't even entered at that point.

Prentice is introduced as "Commander" when he's a Lieutenant Commander - it's a huge difference in the Royal Navy.