In Australia, Jack had used the Oxygen Exchanger to breathe underwater. Here in the Himalayas, he could use it to create more red blood cells. It did this with the help of a red blood cell âaccelerator mistâ, which entered his mouth every time he breathed. As soon as he strapped on the Oxygen Exchanger, Jack started feeling better.
A voice came from beside him. âSecret Agent Courage?â
Jack turned round. There, next to a canvas tent, stood a man. He was dressed in khaki-colored trousers and a long-sleeved fleece with the GPF logo on it. He stuck out his hand towards Jack.
âNice to meet you,â he said. âIâm Alex Bell,â he added, âleader of this GPF expedition.â Jack shook the manâs hand. âWhere are the others?â he asked.
Almost as soon as Jack spoke, three other children materialized: two boys and a girl. When they realized how thin the air was, they too got out their Oxygen Exchangers. Mr Bell walked over to them and motioned for Jack to join him.
âSecret Agent Courage,â he said to Jack, âthese are Secret Agent Storm, Secret Agent Digger and Secret Agent Scarlet.â He pointed to the children one by one.
Jack shook their hands. Secret Agent Storm looked older than him. He had striking blue eyes and strong-looking arms.
Secret Agent Digger was shorter than Storm. In fact, he was smaller than Jack. But he looked tough.
Scarlet, however, was slim and seemed shy. Jack tried not to frown as he wondered why on earth the GPF had called her in for the job.
âRight,â said Mr Bell. âWeâll need to work together on this one. No one climbs alone. The winds can be like a hurricane,â he explained. âThe crevasses are bottomless pits. The icefall is constantly moving. One mistake and you wonât make it home for dinner tonight.â
Jack tried not to let anyone else see it, but he was more than a little nervous. After all, over the last century more than two hundred climbers had died trying to make it to the top of Everest. Jack looked at the other three. He wondered whether they realized how dangerous this mission would be.
Mr Bell pulled out a map. It was a detailed drawing of the route to the top of the mountain. An X marked the spot where they were standing.
âThis is us,â he said, pointing to where Base Camp was marked. âA helicopterâs going to fly you over the Khumbu Icefall and touch down on the Western Cwm.â (He pronounced it âcoomâ.)
âWhereâs the missing plane?â asked Digger through his Oxygen Exchanger.
âNot sure,â said Mr Bell. âWe lost communication north of the icefall. They could be anywhere between there and the Lhotse Face.â
Jack hoped the plane wasnât north of the Lhotse Face. It was tricky; a more than three thousand foot climb up a wall of ice.
âThe scientists discovered the skull here,â Mr Bell explained, touching a point 1,600 feet below Base Camp on the map. âThey took it down to Kathmandu, where they boarded a plane. They were en route to a lab in China when the plane disappeared.â
Jack looked at the other agents. They were listening carefully to Mr Bell.
âI need to stay here to wait for our Yeti experts,â the GPF man said. âIf any of you get into trouble, call me on your Watch Phone. And another thing â weâve got company.â
âWhat do you mean?â asked Jack.
âWe got word that another group is tracking the skull too,â he said. âIt could be the RSO.â The RSO, or Russian Secret Ops, was an international group of agents hired by shady Russian villains to do their dirty work.
âWhy do they want the skull?â asked Storm.
âWho knows?â said Mr Bell. âBut assume theyâre armed with gadgets, and dangerous.â
Jack looked at Scarlet. Her eyes were closed. She looked like she was sleeping.
âWhat are you