A town council counts out the party's reward coin by coin and holds the last few back "for the roof fund." The players barely object. It was a rat job, the sum is small, and they have bigger plans. Write that shrug down, because it's the start of your next adventure. The Pied Piper of Hamelin is one of the cleanest revenge plots in European folklore, and it hands you something villain plots rarely manage: a reason for the party to feel partly to blame when things go wrong. For a lighter folklore hook after this one, the Three Billy Goats Gruff bridge encounter works from the same principle, an old tale with clear rules.
Why the pied piper is a contract story
The Brothers Grimm recorded the version most people know. Hamelin is drowning in rats. A stranger arrives in a coat of many colors and names a fixed price to clear them out, and the council agrees. He plays a pipe, every rat in town follows him into the river, and they all drown. Once the streets are clean, the townsfolk decide they were overcharged and refuse to pay. The stranger walks away.
He comes back on a feast day in different clothes and plays again. This time the children follow. They walk out of town and into a hill, and the hill seals behind them. Some tellings leave a few behind: a lame child who couldn't keep pace, a deaf one who never heard the tune.
The whole story is a billing dispute.
Reduce it to its bones and the structure carries over to any campaign. Someone promises payment and the work gets done. Then the payment is withheld, and the creditor collects on his own terms, at a time he chooses.
In a standard villain plot, the villain's crime drives everything. Here the town's crime drives everything, and the party was standing in the room when it happened. What they said (or didn't say) at that first negotiation decides how ugly the collection gets. That's where the dread comes from. The players aren't hunting a monster. They're accessories to an unpaid bill.
Act one: the rat job that looks like a throwaway encounter
Make it small and dull on purpose. The town of Brennock has rats. Councilor Aldous Venn, who wears his chain of office to breakfast, offers the party solid coin to clear the main granary before the winter stores rot. Pay them enough that they treat it as a real job.
Then make them sweat for it. A swarm of rats in an open field is a speed bump. The same swarm in a granary cellar is a nightmare: low beams that catch on helmets, grain sacks to clamber over, one lantern that gets kicked into the straw on round two. Set the fight in a cramped stone undercroft where the rats pour out of wall cracks and floor drains, so every swing hits brick and every step lands on something moving. The goal is for the party to climb out thinking, "If the whole town is like this, Brennock is finished."
It is. That cellar was one nest of dozens.
The piper is waiting by the granary door when they come up. Tall and thin, in a patchwork coat, a bone pipe hanging at his belt. He speaks to the council and ignores the adventurers entirely. "I can take every rat out of Brennock by sundown tomorrow. Three hundred crowns, and a loaf of bread left on the east wall on the first of every month."
Venn laughs. "Fifty."
The piper doesn't haggle. "Then fifty. And you'll remember the bread."
We strongly prefer running this exchange in front of the party rather than having them hear about it secondhand. They need to watch the town lowball a stranger, watch him take the insult politely, and decide for themselves whether to step in. A table might object on the spot, or it might stay quiet and pocket its own fee. Whichever happens, note exactly who said what.
Once the rats are gone, have Venn pay the piper less than fifty. Or nothing. Nobody puts out the bread. Do it with a smile, while the party is still in town counting its own reward. The piper bows and leaves without a word.
The piper as a negotiator, not a spellcaster
Don't build him as a wizard with a spell list. His one threat is the music, and the music does one thing: it makes people want to follow him. For people, treat it as something near charm person in effect, where the listener warms to him and briefly sees a friend worth walking after. Animals and children simply come.
Tie his power to the scene. In act one he needs no stat block, because nobody should be fighting him. Before each scene, decide what the music can do and state it as a rule ("tonight it reaches every child under twelve within earshot of the east wall"). Then let the players work around it. A fixed rule they can see coming is scarier than a pile of hit points, because they know exactly what's about to happen and still can't easily stop it.
How he behaves matters more than what he casts. He's courteous and reasonable, and he never raises his voice. Confront him and he recites the terms, then waits.
"Three hundred crowns was my price. I accepted fifty. I received eleven. The bread was never left. I'm not angry, councilor. I'm here to collect."
Play that calm straight. Cackling villains are easy to hate and easy to dismiss. A man reading back an unbalanced ledger entry is harder to wave away, because he's right. For more on grounding a villain in one specific grievance, see villain motivations players believe.
The legend never says what the piper actually is, so choose. Fey is the obvious fit: bound by the old law that a bargain is honored to the letter. Our favorite is the spirit tied to the hill outside town, an old thing that has always taken payment from Brennock in one form or another, because it makes the town's history part of the horror. A cursed mortal who once broke a deal and now collects for whatever cursed him also works. Whichever you pick, commit to it, because the answer changes what a renegotiation can offer him.
The timeskip: letting the debt mature off-screen
Cut hard. Months if your campaign moves fast, years if it can stand it. Brennock has gotten comfortable. The granary is full and Venn has won reelection. Ask anyone about the piper and they shrug: "Some vagabond. Got paid, didn't he?"
The same NPC and the same unpaid bill can carry very different amounts of story. Size it to your campaign.
One-scene nuisance
He comes for the party first, as a warning. One night their horses and mules walk out of the stable and up the hill road, with a handful of Brennock's sheep trailing behind. Play it in a single session: a chase through fog toward a thin pipe tune, then a conversation on the hilltop. He'll return the animals if someone carries his message to the council. Short, and the party leaves feeling slightly dirty.
Mid-arc complication
Three nights running, a child walks out of Brennock after dark. Nobody sees them leave. Each morning a single stale loaf sits on the east wall, exactly where the payment should have gone. Now the party has a clock and an investigation. Signal early that force backfires. Say the party ambushes the piper on the second night: he plays louder, and two children go instead of one. The confrontation has to turn into a negotiation.
Full villain arc
The piper never really left. For years he's been teaching Brennock's young people songs, mending their toys, and giving them the attention their parents don't. Teenagers hum tunes they can't remember learning. The final collection is a feast-day exodus, every child and young adult in town walking toward the hill. Swords won't solve this. The party has to renegotiate the original debt with interest, against the clock, while the council squabbles over what it will cost.
Running the confrontation as a negotiation that goes wrong
Before the party meets the piper again, let them find the original terms in writing. This changes the tone more than any other single step. Put it in a council ledger with "50 crowns, piper" written in and "11 paid" scrawled beside it, or have an elderly baker who remembers that the bread never went out. Players who walk in holding the receipt understand they're walking into a debt dispute.
Then let the piper counter. Give the party real options with real costs. The town can pay the full three hundred crowns plus interest for every month the bread was missed. Or it can offer something of equal worth that Brennock values more than coin, such as the granary itself or the council's chain of office. A third path is personal: one of the party enters his service for a year and a day. And if a player invents a fourth option, hear it out; he's a creditor, and creditors listen to offers.
Let them choose badly. Let them try to cheat him and discover that a man who has waited years for his money has already spotted every loophole. If the deal they strike is lopsided, honor it and let the fallout arrive later.
The one outcome to rule out is the party killing the piper and the problem going away. The legend's horror lives in the town's unpaid debt, and killing the creditor doesn't erase what's owed. If they kill him, the children stay in the hill. Maybe the pipe keeps playing by itself every feast day. Maybe the debt passes to whoever sent him, and the next collector skips the courtesy. Killing him should feel like burning the receipt: a good feeling for about a minute, then much worse.
Keep the debt from becoming a one-off
If the party will pass through Brennock again, plant the bargain early and keep it light. A child humming an odd tune in the market. A bare patch on the east wall where bread used to sit. A councilor flinching when a flute starts up at a wedding. For planting details like these so players recognize them later without guessing the twist too soon, see how to foreshadow a twist.
Write down the exact words of the original deal the moment they're spoken. Players will remember "and you'll remember the bread" three sessions later and argue about what it meant, so you want the wording on hand. LorePanic can search your own session notes for the piper's original terms and every scene he's appeared in, so you can read the contract back word for word when the table disputes it.
When the piper finally returns, open with this line before he says anything else: "I've come about the bread."