Translated from the back of the book:
"Lost in Al'Anfa
You can only break a ring of slave traders if you are courageous enough to explore it from within: as a chained slave!
WARNING! 'Lost in Al'Anfa' is the 'hardest' adventure so far for Das Schwarze Auge. New warriors should keep their hands off, for only shrewd and hardened veterans will stand a chance. Cleverness and tenacity are demanded - and will be awarded with more experience points than ever before."
Additional user summary
The heroes are supposed to infiltrate a ring of slave dealers by posing as slaves themselves who are supposed to be bought by their contact in the city of Al'Anfa. When someone else outbids their contact, they find themselves on fields harvesting poisonous crop. Trying to escape, they are tossed into the deadly dungeon alluded to on the back cover text.