Imogen is an adventure game which consists of 16 different chapters. Each of them requires you to complete several puzzles and quests in order to advance to the next one. There is no death for you in this game, but you can also change your character for only a limited number of times.
Spell fragments are to be found in each of these 16 sections of the game, and you must solve every puzzle in order to find a certain fragment of the spell. If you complete the spell you will then be able to escape the caverns in which you are trapped.