Oblivion(Novel) 

The last book reveals Jamie ended up in Saint Boltoph's Church in Boston, England. The other four Gatekeepers are scattered around the world, with Scarlett and Richard Cole ending up in Giza, Egypt. Matt and Lohan Shan-Tung end up in the Basilica de Nossa Senhore de Nazare in Belem, Brazil and Pedro and Scott ended up in the Abbey of San Galgano in Italy.
Ten years have passed since the destruction of Hong Kong, and the Old Ones have revealed themselves to the world, as the war is slowly destroying humanity, and, as predicted, humanity forms a resistance to them, the "World Army." Baker, President of the United States, is opposing this resistance, leading to all out warfare with rebels and government forces. Behind it all are the Old Ones, manipulating events from Antarctica, where they draw humanity with promise of easy victory when in reality Matt has a vision revealing the resistance's defeat. He tries to warn the resistance's leader.
Scott is converted to the Old Ones and lures Matt and Richard into captivity. Richard works out the purpose of the tumi Inca knife and plunges it into Matt, killing his present form but bringing his past form 10000 years into the future to continue the fight. Scott soon regrets his decision and in a final act of repentance reopens the doors, allowing the others to travel to Antarctica, but in the process killing himself. His past form travels to the future along with Matt's and the five are able to defeat the Old Ones once and for all.