Elizabeth Singer Hunt

"Meet Jack and Max Stalwart, Code Names: Courage and Wisdom. Jack and Max are ordinary kids who become secret agents by night, thwarting evil and saving priceless treasures as they solve mysteries around the world. Destination: Brazil. Secret agents Jack and Max Stalwart are sent to the Amazon jungle to investigate the disappearance of an important Global Protection Force scientist. Soon, they discover that the scientist's disappearance is no accident....

Jack, a secret agent on the search for his missing brother Max, must hunt down a stolen map that leads to hidden Aztec gold before ruthless treasure hunter Callous Carl can find it.

A plane carrying a team of scientists has gone missing over Mount Everest. They were thought to be carrying the first true Yeti skull ever recovered -- proof that the Abominable Snowman really existed. Can Jack and his fellow agents use their climbing skills to brave the highest mountain on earth and recover the priceless skull?

Nine-year-old secret agent Jack, called to the Arctic to help find a team of missing animal scientists, tries to stop a rogue organization, Black Arctic, from carrying out their plan to blow up the ice and accelerate global warming.

Nine-year-old secret agent Jack is called to China find a giant panda kidnapped from the Wolong Nature Reserve before the evil Scorpion Gang attempts to sell it on the black market.

Jack is transported to Russia to find the whereabouts of a key aerospace engineer, who turns out to be his father, before the launch of the first manned mission to Mars.

Jack transports to Italy to find out who wants to sabotage race car driver Morgan Parks' chances of winning the Monza Grand Prix.

When the Mona Lisa is stolen, Jack Stalwart, a secret agent with the Global Protection Force, must find it before it leaves the country and is never seen again.