The party meets in Kyholt, where Ninth Truth explains what he wants - following the events of
Internal Error, when Aspexx employees broke through into the gate chamber from a previously-blocked Pentagonal tunnel, there is a possibility to explore more of these tunnels and learn the mysteries of the Pentagonal Civilisation. However, there is also a distinct possibility of Aspexx still being down those tunnels, and Ninth Truth wants to avoid a Diplomatic Incident, so is hiring a party to go in first before letting any overly-keen Borderland/Zeitgeist scientists loose down there.
Ninth Truth first sends them into Kyholt to meet up with Undulating Current, a Zeitgeist scientist who has designed some experimental breathing filters which can help people avoid the horrible effects of the spores often encountered in Pentagonal tunnels - for a little while, anyway. While picking these up, the party also meet Cold Boot, a disgruntled local who's suspicious of Aspexx, and particularly suspicious of Elegant Solution, an Aspexx employee who's recently been hanging around Kyholt trying to get access to the gate - indeed, Elegant Solution also approaches the party and asks them if they would escort her through to the gate.
The party agree to this, though keeping an eye on her, but Ninth Truth is unimpressed when he finds her investigating the gate's surroundings, and promptly bears her off to his office to show her all the excellent public research which has already been done on the gate so she can read that instead. The party are shoo-ed in the direction of the tunnel they're supposed to be going down.
Inside the tunnel, all is much as would be expected by anyone who has entered a Pentagonal ruin before: it's a tunnel, cross-section of an inverted pentagon, carved out of rock. The party walk down it quite a long way before turning a corner and encountering some hostile rockwork, which attacks. Delicate Harmony is able to draw on previously-gained abilities to partially control rockwork, and they are able to disable/destroy the rockwork creatures before they do too much damage.
Another long walk further on, following what appear to be a number of footprints in the dust (though most pointing towards Kyholt, as though more people came this way than later went back), the tunnel turns again and enters what appears to be a broken decontamination chamber (similar to some previously encountered). This one also, however, contains an Aspexx-branded communicator, an Aspexx uniform jacket and a key stamped with the Aspexx logo, all apparently dropped by someone else coming this way. The party leave the communicator behind as Gathering Flow's pilot beacon is blinking - and, at the end of the tunnel, they encounter a handy 'Decay starts here' sign left on the wall by someone else - but pocket the key for later use.
They walk another long distance along featureless tunnels, until eventually they start to notice a feature - small pentagonal mosaic tiles, in five different colours (blue, green, orange, pink and purple) start to appear along the walls, increasing in frequency/density as the party proceeds along the tunnel. It becomes clear that these are leading somewhere - at a junction, the tunnel turns at a corner, but ahead is a dead-end pentagonal room containing a) several mosaic artworks and b) a lot of rather poisonous spores floating in the air.
The party use their breathing apparatus, and their own skills, to enter the room, study the mosaics, make sketches of them and discuss their suppositions. Broadly speaking, these are the obvious facts of the room:
This room looks old, and well-used - the mosaics appear somewhat worn as though by being touched or brushed past.
There are three areas of mosaic - an initial diptych of two simple images, a tetraptych of some more complex scenes, and a final huge single image.
All images feature five five-limbed creatures and the five colours of the mosaic tiles, each one seeming to be linked to one creature.
The party is unable to spend as long as they might like staring at these images, due to the spores, but they make notes and sketches to pass on to Ninth Truth at the completion of the mission (see Aftermath below for details of what knowledge is now publicly available).
Continuing onwards, the party are aware that this is now a very long trek they have been on. How far they now are from Kyholt is underscored when they reach an area where seismic or glacial activity has actually split the land apart, and the tunnel now has a several-meter gap and an offset, with a rope across (apparently left by Aspexx) and ice surrounding the break. Ice which is full of cavern worms. Both characters have ways to get across the gap without difficulty, but run into problems when the cavern worms attack ferociously. Luckily they are finally able to fend them off and continue on their way, only slightly worse for wear.
Following the tunnels (and the footsteps) further, the party eventually end up in a very surprising location - another Pentagonal Gate room. It looks a lot like the ones they have previously encountered, except that in this one there's an Aspexx specialist on a communicator call in an ops tent. The party get the specialist's attention, and everyone asks questions about what everyone else is doing here. It turns out that Aspexx, despite suffering significant losses of the fighting troops sent here with the scientists to protect them, have managed to find this chamber with a dormant gate in, establish an operational base here, and then sneak through to the Kyholt base to try to investigate the operational gate there. They were foiled in really investigating it, but in the months since have finally got to grips with the gate controls enough to get it activated a few weeks ago. The specialist indicates that in fact there's an Aspexx scientist through the gate at the moment, exploring what's on the other side - but before the party follow, she points them at a pile of spacesuits next to the gate. Because the other side of this gate is, somewhat unexpectedly, in space.
Also before they step through, Delicate Harmony interfaces with the gate - which very much impresses the Aspexx specialist. Harmony learns that this gate is connected to one other, and was not actively aware of the two other gates which Harmony has interacted with - the Hive IV gate and the Kyholt gate - but now is.
On the space side of the gate, the party find themselves in another pentagonal gate chamber, recognisably similar to those they have seen elsewhere, except that this one is missing two walls and a chunk of ceiling, through which there is only space. This does not look intentional. There are rockwork creatures here but, as is usual when entering a gate chamber from the gate, they appear to view the party as friendly and do not attack.
With a bit of observation of the strength of light from the star, plus Gathering Flow's startouched abilities, the party conclude that they seem to still be in the Keter system, but likely right on its edge - perhaps within an asteroid belt that encircles the system further out than the (previous) location of the Orion gate.
The party also observe another mural, this one in a different art style and looking much newer (or at least, untouched by regular passers-by). It appears to be made of metal on rock, and seems to show an elongated pentagonal shape among stylised stars and galaxies.
Working together, the party manage to anchor each other enough for Gathering Flow to lean outside the missing walls to see what they can see. What she sees is - beyond the jagged edge of broken rooms and walls like the edge of this room - a smooth, flat surface, with a vertex to another surface at an angle that implies this whole thing might be one huge, broken, pentagonal prism. In space.
Before they can explore further, they are interrupted by a panicked Aspexx scientist, who appears to have met a rockwork Custodian and somehow upset it. All the rockwork comes to attention and identifies the party plus scientist as hostile. A hasty retreat is beaten back through the gate to the Kylal side.
Discussion of all this exciting new knowledge with the Aspexx scientist is cut short by the specialist, who says they were on the communicator with Elegant Solution when the call suddenly cut off, after noises of violence which imply Elegant Solution was- attacked? grabbed? had nebulous bad things happen to her? The Aspexx employees go into total meltdown at this, panicking because Elegant Solution is the daughter of someone Very Important in the Aspexx hierarchy, and they can't be the people who lost her, and how can they possibly get to Kyholt quickly enough, it's hours through the tunnels and-
-Delicate Harmony points out that the gate is now connected to the Kyholt gate.
Aspexx are, once again, impressed by Harmony's understanding of and connection to the gates, and happily accept Harmony's offer to switch the gate's direction. However, they do then look awkward about the idea of charging through the gate into Kyholt while armed and being Aspexx - they appear to be just as keen as Ninth Truth to avoid any potential diplomatic incidents. The party agree to go through on their behalf, find out what's happened to Elegant Solution and get her back.
What has happened is that she has been kidnapped, by Cold Boot and a few friends. They appear to be trying to get information out of her about what Aspexx knows about the Orion Gate explosion, with strong overtones of 'Aspexx caused the explosion didn't you.' Elegant Solution appears confused and sad about this line of questioning and/or the ZAPs they keep taking from an electrified weapon, but doesn't seem to have any information to give over. Once the party manage to break down the door, they deal with this pretty quickly, disarming the attackers and rescuing Elegant Solution and a piece of equipment she had with her. Cold Boot, meanwhile, throws a smoke grenade and attempts to escape, but is caught.