Published in the mid-20th century, 'Doorway to Kal-Jmar' by Damon Knight is a science fiction novel that follows Syme Rector, a notorious outlaw on Mars, as he seeks to uncover the secrets of the ancient city of Kal-Jmar. The city is rumored to contain immense wealth and advanced technology, but it is protected by impenetrable barriers. The story delves into themes of greed and betrayal amidst the remnants of a lost civilization.
