How did medieval people protect their worldly goods? This film is part of the Mobility of Objects Across Boundaries (MOB) network, a collaborative, interdisciplinary project funded by an AHRC network grant, which reconsiders the history of material culture in the period AD 1000-1700. This film starts with an introduction of the MOB project by Dr Leah R. Clark (The Open University) and Dr Katherine Wilson (University of Chester). This is followed by a close examination of medieval keys and a Goldsmiths' chest by Elizabeth Montgomery (Collections and Interpretation Officer) in the Grosvenor Museum, Chester. This film showcases the keys that were important tools in keeping possessions safe as well as an early modern Goldsmiths’ chest, which required two keys to open it.  But what’s inside the chest?