What should I do if something valueble is missing from my room after two guest leave?

Search your home thoroughly before taking any further action.

You say they have priors. Does this come from a reliable source of information?
If you suspect they stole from you, call the police. Taking the law into your own hands leads down a bad road.

I suppose it depends on who they are to you and what worth or value it has. I’d make sure it isn’t just lost somewhere in your home, make polite communications to each of the guests, and if it’s worth enough to involve the police, do – if it’s a very valuable ring, you might want a detective over before you rearrange the scene by searching everywhere. It’s also possible guest #1 saw guest #2 messing with it or something. If nothing else, it’s a good lesson on managing your valuables when guests come over.

I would go further with this. First I would search my home intensely. Then I would make sure to communicate with the two guests. In person if possible since they aren’t returning your calls/texts. I would tell them that you are going to file a police report and you are sure they’ll ask who has been in your house the last couple days so they may be hearing from the police. That you aren’t sending the police to them out of accusation but just because the police told you to notify people that have been in your home. (a small lie but might save the friendship). Then I’d file a police report. It is unlikely the police will do much but it will be on file. Sometimes police do bust thieves and if they do and find your ring then it’ll be on file so they can return it. They won’t likely question your guests but telling those guests the police may be coming might scare them into returning it.

We had stuff stolen from our house as well and now, at a much later date, I wish we would have pursued it. Not because the stuff stolen was valuable but I am still a bit upset that the people idly got away with it and we did nothing.

I like RedPowerLady’s answer. I also hate feeling the “what if’s” and “I should have”‘s after the fact, so if the ring is important to you and/or you think you may see these people again in social or other circles, I would follow through with it.

Like the others said, make sure it’s not just misplaced somewhere in your hme first. Zaku has a good idea when saying that guest 1 may have seen guest 2 looking suspcious, but sadly, unless one points a finger at the other, or the thief confesses, there really isn’t much you can do

If you have a picture of the ring, you could file a police report, but I wouldn’t count on them doing much more than take your information.

After filing the police report,you could take a picture of the ring (if you have one) to the local pawn shops, and tell them to give you a call if it shows up. But that too is probably a long shot. Sorry you lost your ring. But if nothing else, you can use this as a life lesson in trusting others, and be more carefull who you invite over in the future.

Do you have renter’s insurance? If you do, depending on what consider “valuable” it could be worthwhile to file a claim.