Contains all 8 books in the interlinked Zac Power Extreme and Mega Mission Super Series! Mega Missions: Zac Power and his spy agency GIB are facing their biggest challenge yet - but so much of the mission is a mystery! What does Zac's long-lost grandpa have to do with it, and who is BIG's incredible new agent? GIB have no idea what's coming, and only Zac can save the day... Extreme Missions: When Zac Power's grandpa drags him on a new mission in the middle of the night, Zac is pumped. They're racing to find the four parts of a powerful gadget called IRIS. But Grandpa won't say what IRIS does, or why it's been broken up. The only thing Zac knows is that this time, the threat is bigger than to just GIB. If they don't find IRIS before their enemies do, the whole world will be in danger...