Lisa Jackson is a number one New York Times bestselling author who is published in nineteen languages. NEVER DROP YOUR GUARD. NEVER CLOSE YOUR EYES. OR YOU'LL NEVER SEE HIM COMING... It should be the best day of their lives. Too bad they never get to see it. On the cusp of their twenty-first birthday, he strikes. His victims are always twins, their ritualistic murders planned in exquisite detail, down to the moment when they breathe their last together. Detective Rick Bentz had his doubts about the '21' conviction when he worked the case in L.A. Now the real murderer may be loose in his backyard. Twin sisters have vanished, days before their birthday. And as Bentz and his partner Reuben Montoya desperately follow the trail, a killer prepares to unite his next victims in death forever...