The So Blue Marble by Dorothy B. Hughes, Otto Penzler

Griselda doesn't even know who they are, but they know her.  And they are trouble, right from the get-go.  First her landlord ends up dead. Then her little sister is mixed up with them...

American Mystery Classics and Edelweiss gave me the opportunity to read this book for review (thank you)  It has been published and you can purchase a copy now.

They want a small blue marble and they think she has it.  She does, but she hides it.  It's her ex-husband's and she's protecting it.

These two men are deadly.  It seems there are bodies everywhere.  Even her little sister appears to be deadly which is odd at sixteen...

It's a good thing her ex-husband comes home in time to save her.  Or she might have been another victim...