The Yantar may look scruffy and unthreatening but below the surface it's the kind of ship a Bond villain would be proud of.
In hangars below decks lurk submersibles straight out of the Bond film Thunderball. Two Consul Class mini manned subs are on board and a number of remotely operated ones.
It can "undertake surveillance in peacetime and sabotage in conflict", in the words of Britain's Defence Secretary John Healey.
Cable-cutting equipment combined with surveillance and intelligence gathering capabilities make this a vessel to be reckoned with.
Most worryingly though, in its most recent tangle with RAF planes sent to stalk it, the Yantar deployed a laser to distract and dazzle the British pilot.
Matthew Savill, from the Royal United Services Institute, told Sky News this was potentially a worrying hostile act.
He said: "If this had been used to dazzle the pilot and that aircraft had subsequently crashed, then maybe the case could be made that not only was it hostile but it was fundamentally an armed attack because it had the same impact as if they'd used a weapon."
The Yantar is off our waters and here to threaten the West's Achilles heel, says our government. Undersea infrastructure is essential to our hyper-connected world.
Undersea cables are the vital nervous system of Western civilisation. Through them courses the data that powers our 21st century economies and communications systems.
Pipelines are equally important in supplying fuel and gas that are vital to our prosperity. But they stretch for mile after mile along the seabed, exposed and all but undefended.
Their vulnerability is enough to keep Western economists and security officials awake at night, and Russia is well aware of that strategic weakness.
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That is why some of the most sophisticated kit the Russian military possesses is geared towards mapping and potentially threatening them.
The Yantar's concealed capabilities are currently being used to map that underwater network of cables and pipelines, it's thought, but they could in the future be used to sabotage them. Russia has been blamed for mysterious underwater attacks in the recent past.
A more kinetic conflict striking at the West's soft underwater underbelly could have a disastrous impact. Enough damage to internet cables could play havoc with Western economies.
It is a scenario security experts believe the West is not well enough prepared for.
Putting the Yantar and its Russian overseers on watch is one thing; preventing them from readying for such a doomsday outcome in time of war is quite another.
(c) Sky News 2025: A Bond-villain ship prowling our waters: Why the Yantar alarms the West
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