“ A casual remark by one of the party about something met on a previous adventure leads to a summons to and grilling by the Mages' Guild (or equivalent), probably resulting in an expedition back to that area to recover the things for study by the Guild. The party's presence will be 'requested' for this expedition.”
“ It looks like a cook's book. It is a cook's book. It is also where the cook, who happened to be a master spy, encoded all his secrets and contacts. The book has innocently fallen into your group's hands. Everyone wants it, and many are not subtle or peaceful in their attempts.”
“ Medieval Britons didn't write contracts. Instead, men making agreements would clap their knives onto an altar and recite the agreement three times to seal a deal. Even after the Normans introduced written contracts, British nobles would wrap the parchment around a knife to authenticate it.”