The only other Jane Perry story that I've read was a novella that was a pretty straight-forward police procedural. This is a little different.
Jane Perry is a Denver homicide detective, who has had great professional success but a very rough personal life. She's recently met a man she's really connected with for the first time, and has kicked the alcohol and cigarettes that have had too much control of her life.
And she's discovered she has an older half sister, born and given up before her mother made the mistake of marrying Jane's father.
Knowing starts with Jane leaving on a road trip to go meet her half sister in New Mexico, where she's currently living in halfway house.