This demonstration shows how an OO DBMS can be extended for taking into account multimedia data. An integrated environment for multimedia presentation authoring and playback has been developed on top of the O2 OO DBMS. It consists of a library of classes which can be used and shared by several multimedia database applications. The system has been developed using C++ and multithreading is used for performing parallel tasks. In addition, a graphical interface has been developed which allows to easily and interactively build multimedia presentations. Also, a video data model has been specified and implemented. Finally, a query language like OQL is used to query video and presentation objects and to automatically generate dynamic multimedia presentations.