Station III
"Machinery hums behind high steel walls. Up the hill, there are visible outlines of warehouses and a building with a spire. But the lamps are low where they burn at all, and your ship the only one in harbour."[1]
Station III is a top-secret facility located on an island in the Unterzee.
Nothing to See Here
"On the very edge of London's influence, curious matters are conducted."[2]
Station III is a mysterious location occupied by whirring machinery, sprawling warehouses, and a tall, spired building, all surrounded by a high metallic fence.[1] The gate of this fence is notably cold to the touch and is nigh-indestructible, repelling even the finest of chisels or the mightiest of crowbars.[3]
The only evidence here of outside visitation includes a strange burner for incense, a log book detailing an enthralling song, worn ironmonger's tools, and broken medicine bottles and clumps of silvery metal, with a torn label reading "SOOTHE & COO...".[4]
Most curiously, any reports of this location's activities are ruthlessly censored by the Admiralty and the Ministry of Public Decency.[5]
Heartmetal
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"What use is heartmetal to you? But then, what use is a Long-Box? (Perhaps you imagine the whisper at shoulder - 'What use, indeed, is a heart?'. When you turn, there's only the ragged flirting of the wind.)"[6]

Station III is the manufacturing hub of a strange, silvery substance called heartmetal.[7] This material is extremely strong, icy to the touch,[8] and is considered dubiously legal to trade or possess, assuming the law even acknowledges it exists at all.[6] Its durability means it has a variety of practical applications,[9] but the means of producing heartmetal are kept strictly secret, for a very good reason.[10]
Heartmetal production is primarily managed by a company called Soothe and Cooper,[11] named after its founders, who have a workshop of their own at Station III.[12]
Extraction
"On first sight, it looks like a tomb-colonist coffin. On closer examination, it carries stencilling reading SOOTHE & COOPER and a handwritten tag: 'DELIVERY TO DEPOT (A), STATION III'."[11]
"Excellent, I'm going to need a scalpel and pliers."[13]

To begin production of heartmetal, Station III primarily relies on a steady supply of corpses stuffed inside Soothe & Cooper Long-Boxes,[11] which have been delivered to the Station for generations. These specialized coffins are brought in mainly from the Surface,[14] though they can also be found at other locations across the Unterzee, such as the Shepherd Isles,[15] Venderbight,[16] or certain shops in Khan's Heart.[17]
The corpses inside the long-boxes are considered permanently dead,[18] and are processed by the workers of Station III, called acolytes,[19] who use scalpels to carefully dissect the bodies and extract the metallic deposits within. These metallic spheres are layered like gobstoppers, so the acolytes crack them open to obtain their valuable, heavy cores, which are then placed in jars marked with the Correspondence.[20] The useful ones are then marked for export.[21]
Secrets and Tonic
"SUFFERING HEART-ACHE? A SOOTHE & COOPER tonic for the dysphoric, despondent and depressed! Equally good for catarrh. CONVENIENT, SCIENTIFIC, INFALLIBLE!"[22]

The deceased brought to Station III habitually took Soothe and Cooper's Heartsease Tonic during their lives; this medicine is advertised as a cure for sadness,[22] and for keeping secrets unspoken. It is a strange liquid with a silvery color, and when spilled, it hardens like ice into a cold,[8] brittle, and very sharp substance.[23] The tonic is manufactured by Soothe in his workshop, where he melts leftover heartmetal shavings in a cauldron for later bottling.[12]
Soothe and Cooper's Heartease Tonic is usually consumed with wine or laudanum, but can be directly imbibed as well. Once in the body, it produces a chemical reaction with the drinker's soul, covering the source of a person's woes and slowly hardening and accumulating over time. This process creates metallic spheres that may form anywhere within the body,[10][24][25] though the most common place of the metal's accumulation is right over the heart, resulting in the substance's name.[20] Unfortunately, consumers of Heartease Tonic often grow dependent on it, allowing the metal orbs to grow and grow until they risk rupturing internal organs.[10] Rubbery Men can fall under the effects of Heartease Tonic, though unlike humans, their secrets manifest in the form of black amber within their bodies.[26]

The specific location of heartmetal buildup can vary depending on the nature of a person's secret. For example, if a person listens to secrets regularly and does not speak them, the deposits may accumulate in their ears and tongue,[27] while if an academic keeps a discovery hidden, the deposit may develop within their brain.[24] The cores of these heartmetal deposits contain a person's deepest secret, crystallized in the form of a black substance, and may vary dramatically in size depending on the intensity of the secret.[28] Exposure to said pellet can make a person relive the memories and feelings associated with that secret, which can be extremely disorienting,[25] so the acolytes of Station III consider it of utmost importance to sing while they perform their duties; not doing so can result in a free reservation at the Royal Bethlehem Hotel.[29]
Usage and the Heartmetal Smith
"Nothing like it for weaponry. Does more damage than any ordinary steel, and a little bit of the shrapnel will give you trouble to the end of your days."[9]
The Masters of the Bazaar are very interested in heartmetal pellets related to love and romance,[30] and they're the ones responsible for the creation and arrangement of Station III.[14] Any heartmetal bits that aren't useful to them, however, are thrown to the Station's dump,[31] which is sometimes visited by marauders and thieves.[32] The Echo Bazaar has a hand in the business of Station III,[33] but it also seems to have a heartmetal operation of its own that's independent from the island; many Soothe and Cooper Long-Boxes can be found deep within the Bazaar's bowels, and can be sold legally to Crawcase Cryptics for a good sum.[34]

The Heartmetal Smith is a mysterious individual who is capable of working with discarded heartmetal to forge products for export.[35][36] He often creates products suitable for maritime combat, such as ammunition, hull plates, and harpoons; according to him, heartmetal weapons are more powerful than their steel counterparts, and their shrapnel can cause chronic ailments that last for a lifetime. Unfortunately, the hardness of heartmetal tends to wear out his tools quickly.[9]
By his own account, the Smith came to Station III by swimming.[37] The Smith toils without complaint in the solitude of his workshop,[38][39] with a heartmetal locket and chain always fastened around his neck - but his ultimate goal is to forge a suit made of heartmetal, so that he may walk where he came from without experiencing the grief of others.[40]
The Austere Acolyte
"There's a story I heard when I first apprenticed here. That there was someone who worked here who swallowed one of the black pellets, and it made them impervious to grief. There was nothing they could see that was worse than what they already knew. I think that would be a great strength to have, don't you?"[41]
The Austere Acolyte is one of Station III's most accomplished workers, possessing a wealth of experience in heartmetal production and the skill to process the Station's trickiest specimens.[42] She works in the spired building that looms over Station III, and can almost always be heard singing a nonsensical, cheerful tune to drown out the torrent of memories and emotions released from heartmetal.[43] She works in protective clothing, as well as goggles with special lenses that allow her to view the secrets stored within heartmetal pellets with ease.[44][45] She also has a group of sturdy Clay Men assistants who help her with transporting the heavy Soothe and Cooper Long-Boxes to her workshop.[46]
The Acolyte doesn't remember how she came to work at Station III.[47] She does remember her former life as a doctor in London, however, along with her bohemian twin sister. Her sister lived with her for a time, but died in an accident involving a shared dream. The Acolyte tried to save her, but believes that she unintentionally killed her sister permanently in a failed resuscitation attempt, leaving parts of her body severely wounded in the process. Now, she regards her current work as penance for her past mistake.[48][47][49]
The aforementioned story is in fact not the complete truth. The Acolyte never had a twin sister, and the entity living with her was actually a mysterious creature drawn to her potential, wearing a "mirror" of her face.[50]
References
- ↑ 1.0 1.1 Location description, Sunless Sea
- ↑ Item description, Sunless Sea
- ↑ Try the gate, Sunless Sea
- ↑ Search for signs of other visitors, Sunless Sea
- ↑ Station III, Sunless Sea
- ↑ 6.0 6.1 Exchange a Long-Box for a Heartmetal Ingot, Sunless Sea
- ↑ Item description, Sunless Sea
- ↑ 8.0 8.1 Break into the warehouse and leave the box there, Sunless Sea
- ↑ 9.0 9.1 9.2 Deliveries to the smith (0), Sunless Sea
- ↑ 10.0 10.1 10.2 Ask how the metal balls are formed, Sunless Sea
- ↑ 11.0 11.1 11.2 Item description, Sunless Sea
- ↑ 12.0 12.1 A visit to Soothe & Cooper, Sunless Sea
- ↑ Soothe & Cooper Long-Box, Fallen London
- ↑ 14.0 14.1 Ask where the corpses come from, Sunless Sea
- ↑ A Retired Monster-Hunter wants something to remember his glory days, Sunless Sea
- ↑ Explore Venderbight, Sunless Sea
- ↑ Purchase a Soothe & Cooper Long-Box, Sunless Sea
- ↑ Story description, Sunless Sea
- ↑ Return later, Sunless Sea
- ↑ 20.0 20.1 Watch with medical interest, Sunless Sea
- ↑ The wife, Sunless Sea
- ↑ 22.0 22.1 SUFFERING HEART-ACHE?, Fallen London
- ↑ Story description, Sunless Sea
- ↑ 24.0 24.1 The Professor, Sunless Sea
- ↑ 25.0 25.1 The sister, Sunless Sea
- ↑ The Rubbery Man, Sunless Sea
- ↑ The Confessor, Sunless Sea
- ↑ The drinker, Sunless Sea
- ↑ Ask why she sings, Sunless Sea
- ↑ A historian, Sunless Sea
- ↑ Ask what becomes of the contents of the balls, Sunless Sea
- ↑ Watch until you know what they're up to, Sunless Sea
- ↑ Surrender a Long-Box for payment, Sunless Sea
- ↑ Pilfer a large, mysterious box, Fallen London
- ↑ Deliveries to the smith (1), Sunless Sea
- ↑ Search the place on your own, Sunless Sea
- ↑ Ask the smith about how he got here, Sunless Sea
- ↑ Ask the smith about life on the island, Sunless Sea
- ↑ Story description, Sunless Sea
- ↑ Ask him about the heartmetal suit, Sunless Sea
- ↑ Ask what she thinks of the work she does, Sunless Sea
- ↑ Find out what she wants, Sunless Sea
- ↑ Carry the box on to the building with the spire, Sunless Sea
- ↑ Send ahead to the building for extra hands, Sunless Sea
- ↑ Story description, Sunless Sea
- ↑ Story description, Sunless Sea
- ↑ 47.0 47.1 Ask how she came to be here, Sunless Sea
- ↑ The Time Before, Sunless Sea
- ↑ Press for more details, Sunless Sea
- ↑ Shades of Black, Sunless Sea