Against the Cult: Getting Away with It (1.8a)

Theran cautiously opens the door; the main basement room is large and dark and empty of any other people. Seeing it through elven eyes rather than spider ones, the experience is very different, but the room appears largely unchanged. The door opens 5' from the northern wall (on Theran's left), apparently sharing that wall with the wine cellar room where Myrtha and Reptile are still lugging the body. The room extends about 50' deep to the east, supported by two pillars in the center of the room, and is about half that wide. The northern wall sports many torch brackets, though some don't have torches and none of the ones that are there are lit. A staircase leads upstairs on Theran's right, and on the other side of that, there is another door mirroring the one that Theran has just opened, 5' from the southern wall. The southern wall is jumbled with various pieces of furniture - mostly tables and chairs - some of them broken. The ceiling is supported by heavy rafter beams, festooned with many cobwebs.

Myrtha looks around in the lantern's light and realizes that she hasn't seen Whiskers since they opened the cellar door.

Both Reptile and Myrtha hear shouting from outside, but the thick door and the distance down into the wine cellar muffles and distorts the sound, so they can't make out words.

Theran is in the main basement room: a large space with some items to explore.
Reptile, Myrtha, and the mutilated body are in the Wine Cellar, a smaller room with various casks, barrels, and tuns of beverages that could be investigated. The stairs to the outside are in the Wine Cellar.
The Wine Cellar connects to the main basement via the door Theran used; there is another closed door to the south of that one in the main basement.
There are also the stairs up to the Inn in the main basement room.

As Myrtha and Reptile are stuffing the body behind a wine cask, all three Dungeon Busters hear a shout from outside, from someone who is yelling loud enough that even though the words are muffled by the door and the sound bouncing down the stairwell, they can still make out the meaning: "...GET OUT OF HERE ALAN! SAVE YOURSELF! YOU HAVE A WIFE AND KIDS!!" then there is a clatter and clash of metal.

@GeneCortess - which stairs are the ones that Reptile's moving to?

The rafters are thick and the ceiling is finished, so the movement of people on the ground floor above you would not be obviously audible. Theran has shared that the basement stairs (as opposed to the Wine Cellar stairs) lead up to the kitchen door, and there was only one person in the kitchen when he scouted it yesterday.

It's tough to say how far the fight outside is to the Wine Cellar door without climbing the stairs and listening, but you think it's pretty close. It is the middle of the night, so slipping back outside unnoticed through the Wine Cellar door might be possible if the combatants are far enough away and you don't carry a light source with you...Theran would have the best chance, given that he has darkvision.

Let me know if that doesn't answer your questions.

Theran, meanwhile, sees some small object on the floor at the other end of the room. Is it something that someone dropped?

Reptile mounts the Wine Cellar stairs back to the door held in place by the bar (where the Dungeon Busters entered moments earlier). He hears combatants in a fierce fight.
Amidst the sound of blows and clashing weapons, someone is saying: "What part of fighting should be fair, Grover? You know who complains about not getting a fair fight? Losers. Losers like you will never belong in Orlane!"
Another person says: "There's someone else out there! A bowman in the dark! Let's finish this quickly for her!"
A third person says: "Get away and get help Alan! Don't worry about us! Why are you and Hulbar fighting against a fellow dwarf? What hold does Grover have on you?"

Thinking back, Myrtha and Theran spent a fair amount of time during the previous day talking about the layout of the Inn, refining details and clarifying discrepancies. It's clear to everyone that the "door out of the storeroom" that Theran mentioned is the door they just used to enter the cellar; namely, the Wine Cellar Door (where Reptile is now). What Theran remembered of the whole Inn's layout is depicted in the maps thread; each character has that rough understanding of what he could see as a spider.

Meanwhile, Theran examines the small object he sees on the ground.