Disclosure: I received this book via Goodreads' Early Reviewer program.
Ronald J. Allen has been a professor at Christian Theological Seminary in Indianapolis for nearly three decades. He has written a number of books on both of his teaching specialties, preaching and the New Testament.
His latest, published by Eerdmans, is a very readable introduction to the New Testament. The heavy theology is in there, but it is presented in a very clear manner, a feat that not every academic manages. The book is written to be accessible to the unchurched, and is successful in that. Yes, the first few pages include a "how to read the Bible" section that is very simplistic to anyone who has ever picked up a Bible, but after that the book has much in it that "church veterans" can benefit from.
Topics covered in the book include the world of the New Testament, the authors of the books, and how the Bible came to be the book it is today. He then moves on to discuss the life of Jesus, the books of the New testament, and then ends with discussions of "big ideas" and "famous passages" from the New Testament. Each chapter has discussion questions designed to spur conversation about the material, either in a one-on-one setting or a Bible Study or Sunday School class. The four appendices are also helpful resources, especially the discussion of the various Bible translations.
Allen has a perspective on these topics, as every author of a theological work does. What makes his approach useful is that he discloses his perspective, and then presents all of the major positions in an even-handed manner. Again, his approach is to be open to the unchurched, so not hewing solely to one particular theological viewpoint is wise.
There are not many books out there that meet the niche that this one does. The combination of the modern, academic viewpoint and the very readable nature of the writing makes it a very successful work.