I've been running the adventures in Candlekeep Mysteries lightly reskinned for my Krevborna setting. The characters are all employed as members of Creedhall University Library's "Special Collections Department," aka adventurers. This is a recap of what happened in "The Curious Tale of Wisteria Vale." Fair warning: spoilers lurk below.
Elsabeth, human paladin played by Anne
Rufus, human barbarian played by Steve
Gnargar, kobold monk played by Heather
Rising Leaf, human monk played by Michael
Elsabeth, Rufus, Gnargar, and Rising Leaf were pulled into a meeting with Horatio Lupa, their superior in the library, and a member of the Rooks named Rilka. They all knew about the Rooks' reputation; they are bounty hunters and thief-takers for hire, but also can be hired for less savory work such as strike-breaking. The group was shown an oversized green volume that looked like the text of a play.
Rilka explained that years ago the Rooks had trapped a member of their organization named Arrant Quill inside a demiplane bound to the book when he had become infected by an evil influence. This was intended to keep him sequestered until a cure could be found. The cure had now been found; Rilka showed them a crystalline dagger with an inner light that beat like a heart. To free Quill from evil, the dagger needed to pierce his flesh. Unfortunately, the Rooks had lost the knowledge of how to enter the book's demiplane. Rilka offered them a substantial amount of money to figure out how to enter the book's demiplane and deliver the cure to Quill.
Left to their own devices, the group decided to read the play for clues. The play's plot concerned a young man named Vargan who was slashed across the face by a cruel lord after his village was burned to the ground. Vargan swore to seek revenge. In the second act, he joins a Rooks-like organization and tracked down the cruel lord, killing him during a feast at the lord's manor. However, in the third act he comes to believe that his allies have gotten too powerful and plots to betray them; they imprison him in another world. Something less than allegory is clearly being expressed here.
Following a clue they gleaned from noticing that a particular line of the play had been underlined, they shined a light on the book through the crystal dagger they were given, which revealed the phrase "Rooks at twilight." They followed a bunch of potential leads, such as staking out the Rooks' headquarters at twilight and visiting a bar called The Rook's Rest, where they led a bunch of drunken students in performing the play.
The secret of the book was cracked when Leaf said "Rooks at twilight" out loud, which caused pages to tear themselves out of the book and rearrange themselves into an arched doorway. Pushing through the archway allowed the party to enter what appeared to be an idyllic, too perfect farming community surrounded by a pine forest. The group were spotted by a mob of strangely clean peasants who pointed at them and yelled "Outsiders!" The peasants began to approach, but they didn't have violent intentions. Instead, they began hugging the party in welcome.
When asked about Arrant Quill, a peasant woman holding a basket of bread told them that he was the kindly lord of the land, not the tyrant they supposed. The peasant also pointed out Quill's manor house at the northern end of the village. The front door of the manor house was locked and ringing the bell and knocking did not get anyone's notice, so Leaf kicked the door in. Two paintings in the lounge caught their interest. One painting showed a handsome man wearing luxurious clothes with a scar on his face; this was presumably Arrant Quill. Alongside this man was a woman whose face had been scratched out with black ink. Elsabeth realized that the woman was likely a younger Rilka. Elsabeth also discovered that the landscape painting of a forest acted as a portal to an extradimensional space.
Forgoing extradimensional tomfoolery for now, the group continued to explore the house. They found themselves in a kitchen, where a cook was preparing food for a feast that was to be held at the manor later. Gnargar stole a few sandwiches. Elsabeth learned that Arrant Quill didn't have a scar, at least according to the cook, as he did in the painting.
It was decided that Leaf and Gnargar would enter the painting while Rufus and Elsabeth stayed behind. Inside the painting, Leaf and Gnargar found themselves in a room where the walls had been painted to resemble a forest scene. Confusingly, there were three doors in the room, each of which seemed to lead to other extradimensional spaces. The room where a massive bird of prey was lairing was studiously avoided. They instead chose to enter a room laid out with a banquet. The pair began to experiment with the food. Eating steaks made them feel healthy and empowered. However, when Leaf ate a cheese-stuffed pepper, he immediately passed out.
Leaf eventually revived, much weakened by the experience, and the pair resumed their explorations, which culminated in finding Arrant Quill lounging on a fainting couch. He asked them if they had any food or water; Gnargar gave him a cheese-stuffed pepper, which caused him to immediately pass out. Leaf slung the unconscious Quill over his shoulder and they entered another door. This one led to a room inside the manor house where peasants from the village were gathered at the promised feast.
Stepping inside, they found that there was another Arrant Quill attending to his guests--this one quite awake and ambulatory. Rufus and Elsabeth heard the commotion and quickly joined Gnargar and Leaf in the ballroom. This second Arrant Quill was quite astounded that they were carrying someone who looked exactly like himself. He also mentioned that the ball was being held in honor of Lord Renekor. The assembled peasants referred to Lord Renekor by a number of alternate titles, such as "The Lord of Eyes" and "The Watchful Lord."
Elsabeth used some of her healing magic to revive the unconscious Quill. The two Quills began to circle each other, each regarding the other as an imposter. The peasants were happy to eat, drink, and watch the uncanny spectacle of two Quills ready to go at each other's throats. As if things couldn't get much worse, Lord Renekor's arrival was heralded by the sound of a trumpet. Lord Renekor proved to be a beholder wearing an Elizabethan ruff. Oddly, when presented with the crystal dagger, he begins to quote from Macbeth. At one point, Lord Renekor broke the fourth wall and cast a glance and a comment to an audience that wasn't there.
The party tried to draw the Quills to another room for a covert stabbing, but the two could not be pulled away from each other and Lord Renekor was poised to intervene. Something clearly had to be done, and being members of the Special Collections Department, that something was violence. Elsabeth, Rufus, and Leaf engaged Lord Renekor, while Gnargar attempted to stab the Quills with the crystal dagger. Their foes proved to be extremely deadly. Lord Renekor's eyestalks afflicted the group with a variety of ills. The Quills' cutting remarks caused massive psychic damage. Rising Leaf was taken out with a magically empowered comment on his drinking habit. Grangar was almost turned to stone by one of the beholder's rays, but was spared due to the salted egg he had eaten earlier. Elsabeth managed to slay Lord Renekor and Gnargar stabbed the real Quill with the dagger, which emptied its curse-lifting magic into his bloodstream.
With Arrant Quill cured of his evil infection, the demiplane began to unravel. The group found themselves back in The Rooks' Rest, now long after closing time. With them was a confused, but restored, Arrant Quill. The party helped themselves to the "open bar" before taking Quill back to Rilka and receiving their rich reward from the Rooks.