Look for the items displayed at the bottom of the screen, and click them. Use the items to continue your quest. Click the question marks or the hint button if you need help.
Source
https://www.zylom.com/us/en/download-games/hidden-object-games/mortimer-beckett/mortimer-beckett-and-the-crimson-thief/
Mortimer Beckett and the Crimson Thief screenshots
