Angels: Who They Are, What They Do, and Why It Matters is a book by Jack Graham, Senior Pastor of Prestonwood Baptist Church. It was originally published in 2016 by Bethany House Publishers.
The central theme of the book is (as the title suggests) the concept of angels as outlined in the Bible. Dr. Graham was encouraged by the publishers to make this the topic of his next book after the success of his previous one (Unseen); he was reluctant to do so for three reasons: 1) he considered the topic to be a "fringe" one, 2) he believed he had covered all there was to say about the topic in a chapter from Unseen, and 3) all his prior books were based on sermons or sermon series he had done, but he had never covered this topic in any sermon series. But he was encouraged to do so by a married couple who were friends (the wife was battling cancer and would pass away before the book was published).
One of the notable stories in the book is the account of a possible angelic visit to former The 700 Club co-host Sheila Walsh (who is a Prestonwood member): a mere 12 hours after hosting an episode of the show she would check herself into a psychiatric hospital, and would be visited by a strange man who gave her a stuffed lamb and told her "Sheila, the Shepherd knows where to find you"; during her entire one-month stay she never saw the man again.