It's become apparent that at least one member of my S&S game has read sections of the AP. The character has now acted upon information I have not revealed several times, and knows exactly what to seek out and how to obtain it. The player failed to reveal this fact to me during recruitment and character creation; it is not something I would have allowed if I had known.
So now I find myself with a player that knows what to expect next. How should I deal with this?
Cut the player after a talk or change the adventure (either changing the expected or adding in things that are perfectly suited to the other characters).
I do recommend talking with the player.
Unfortunately I can't really change the adventure too much. I agreed to run a published AP knowing I wouldn't have enough time once classes start to create my own campaign content.
I was thinking of changing it in ways that are easy for you, but means that the player doesn't have a win button. Moving where the secret treasure is, switching the names of two npcs so the one that is good and helpful has the evil ones name and vis versa.
But if you want to be able to run exactly how it is printed and it bothers you that the player knows what is coming, then you really only have the option of asking them to leave the game.
(And if you don't have much time, you can normally toss a "How do I change this to confuse someone who read the adventure post up on the boards" - you'll probably get more answers than you need :)
Hate that. I made the mistake of reading an adventure before I played in it and was soooooooo bored playing I never did it again. I don't know why anyone would do it intentionally and miss out on all the surprises and the reward of finishing a story using your own brain. Spoilers suck.
chavamana's advice of talking to the player is solid, but why not have a little fun at the player's expense before you do? Little things you can do that don't require to much effort on your part: Move treasure, encounters, traps and secret doors to different locations but keep them the same. The PCs who haven't read the adventure will have the same amount of fun/difficulty and the out of game knowledge will be all but useless for the player who has. If the PC is "investigating" an area that his out of game knowledge leads him to believe is where loot or a secret door is put a trap there instead... see how many traps he sets off.
"Dream sequences" or hallucinations are a nifty little gimmick too. If there's a part that he's expecting to play out a certain way throw a giant curve-ball at him like a lich where there is supposed to be an empty room for example. As an added benefit this lets him know that his metagaming hasn't gone unnoticed, at the very least, he'll keep the metagiming down to minimum since he won't know when you're going to throw your next curve-ball.
Example of who this works in game:
>GM: "You all wake fully rested and make your prayer and memorize your spells etc. You're now ready to continue exploring the dungeon."
>Metagamer: "I go to area D14, where the kobolds and Spear of Awesome-sauce is."
>Rest of the party:".... that sounds like a good idea."
>GM:"You go to area D14 where the kobolds and Spear of awesome-sauce should be and encounter a level draining Wight! Roll for initiative."
>Metagamer:"But we're only level 1!"
>GM: "Tough s%&*."
*proceed with party-wipe encounter*
>GM to metagamer: "You wake up a howl from a terrible dream about being mauled by a wight. You're exhausted from your restless night. Take a -2 penalty to your attack rolls until you can rest again."
>Gm to the rest of group:"You all wake fully rested and make your prayers and memorize your spells etc. You're now ready to continue exploring the dungeon."
>Rest of party: "We avoid area D14."
Checked with the player: He didn't truly read the AP, though he admits to flipping through it and making an art-pass. I can tell he picked up more than just the art, though, probably without realizing what else he was seeing around the images.
I'll try to keep this in mind going forward, though I worry what impact this might have for major fights at the end of chapters and volumes. These encounters are often well-illustrated, and the player admits that he tends toward metagaming.
Checked with the player: He didn't truly read the AP, though he admits to flipping through it and making an art-pass. I can tell he picked up more than just the art, though, probably without realizing what else he was seeing around the images.
** spoiler omitted **
I'll try to keep this in mind going forward, though I worry what impact this might have for major fights at the end of chapters and volumes. These encounters are often well-illustrated, and the player admits that he tends toward metagaming.
As long as you are onboard, switch names and alignments of the NPCs... that should prove unsettling^^ Otherwise, just switch encounters, or have monsters appear from different places.
Shouldn't be too much work