Carter has to wait a month for a ship from Oriab.  He tries to spend the time productively, asking after Kadath and his mysterious dream-city, but nobody admits to knowing anything.  One old merchant looks all shifty and changes the subject when Carter brings it up.  This guy used to trade with the folk of Leng, a distant stony land supposedly haunted by the High-Priest Not To Be Described, whom Lovecraft describes as wearing a yellow silken mask over its face.

Meanwhile one of these black ships comes in and Carter gets to see firsthand how transparently the merchant-sailors aboard are devils dressed in disguise, and how they are pretty clearly buying fat Parg slaves and eating them.  Carter finds them repugnant, of course, but one of them approaches him.  He’s been asking all kinds of questions about Kadath, the devil-sailor says.  Everybody’s talking about him in the bars.

What of it? asks Carter.

This devil-sailor might know a thing or two about Kadath, if Carter’s interested.

Of course Carter’s suspicious, but he can’t pass up an opportunity to learn about Kadath, no matter how slim the chances are that it’s not a trap of some kind.  He invites the devil up to his room at the hotel, and tries to get him drunk on moon-wine, since that worked well with Atal.

The stranger drinks all of Carter’s wine without displaying any impairment, then pulls out a flask and offers Carter a nip of the stranger’s own spirits.  The flask, Carter notes, is carved from a single ruby crystal, marked with all kinds of evil-looking heiroglyphs.  However Carter feels he should be polite, and takes one tiny sip, and of course he passes out immediately.

Carter comes to on the deck of the black ship as it speeds across the Southern Sea.  He isn’t tied up, but three of the devil-sailors keep watch over him.  Helpless, Carter watches as all kinds of Southern islands and nations fly past: Zar (nice towers), Thalarion (ruled by the divine spirit Lathi), Zura (big on earthly pleasures), Sona-Nyl the blessed land of fancy.

The ship travels at weird impossible speed past all these gorgeous lands, in less than a single day.  Carter deduces from their heading that the ship must be making for the Basalt Pillars of the West.  Some people say the lovely nation of Cathuria lies beyond the Basalt Pillars.  Lovecraft wants us to know that those people are idiots.  The Basalt Pillars mark a hole in the world, a monstrous cataract wherein the oceans of Earth’s dreamland drop wholly to abysmal nothingness and shoot through the empty spaces toward other worlds and other stars and the awful voids outside the ordered universe where the daemon sultan Azathoth gnaws hungrily in chaos amid pounding and piping and the hellish dancing of the Other Gods, blind, voiceless, tenebrous, and mindless, with their soul and messenger Nyarlathotep.

Carter realizes these devil-sailors must be agents of the Other Gods, which would explain their obvious evil traits.  They heard about his dream-quest for unknown Kadath, figured their masters the Other Gods would want to punish Carter for his temerity.  So they shanghai’d him and even now they bear him off to claim whatever bounty the Other Gods will pay.

At dinnertime the devil-sailors offer him some stew, but he’s suspicious that it’s Parg slave stew and doesn’t partake.

Then, boom!  Through the pillars and into space!