After Indiana Jones left Marion Ravenwood a week before their wedding, she gave birth to a son who she named Henry Jones III. Marion went on to marry Colin Williams, who Mutt was led to believe was his biological father. Mutt also befriended Professor Harold Oxley, who became a surrogate father to him when Colin was killed during World War II.
Search for Oxley
When Oxley went missing in Peru, Marion followed and ended up disappearing as well. She managed to get a letter to her son telling Mutt to find Jones. He caught up the archaeologist just as he was leaving on a train to New York City, having decided to leave the country for London.
After convincing Indiana to come along with him, they go to a diner, where Mutt delivers a letter sent by his mother, "Mary Williams". But then two KGB agents who were watching tried to capture the duo, only being stopped by Mutt starting a fight between the Greasers and Socialites. The archaeologist and his new sidekick get away on Mutt's motorcycle, and a chase through the Marshall College campus begins, ending when one of the two persuing Russian cars crashes into the statue memorial of Marcus Brody.
After Indiana and Mutt solve the riddles written in dead language from the letter, they go to the possible location of Oxley - Nazca, Peru. There, in an old spanish tomb, they found a Crystal Skull that Oxley had returned to where he had found it.On their way to the tomb Mutt gets stung by a huge scorpion and thinks that he is going to die but Indy tells him not to worry, the bigger the scorpion, the better. As they were leaving the tomb, a group of Russian agents captured them. The agents took them to their camp, where Mutt was reunited with Marion. Unfortunately, Oxley was also at the camp, and was insane from the Crystal's power.
Mutt later created a diversion for the group to escape, but they were recaptured. After this, his mother told him that Indiana was his real father. The group later made another escape attempt, during which Mutt fought Irina Spalko. After escaping the Russians, the group came to the temple where the Crystal Skull was supposed to be returned, where the Russians caught up with them again. When the Crystal Skull's power was activated, the group escaped again.
Mutt later attended his parents' wedding.
Adulthood and further adventures
When Mutt turned 20, Indy considered him an adult, especially after his son Rover was born.
Mutt served in the Vietnam war as a United States Air Force Captain starting in 1963 and ending in 1966, being promoted up to Major, but had been ordered to leave because of an injury he sustained to his right arm.
Mutt didn't want to leave, and snuck out of the field hospital he had been held in, just to kill more enemies, but when he stepped out of the tent, his left foot landed on a mine, and his left leg was burnt badly, but still attached to him forcing him to finally go home.
Near death situation
When Mutt was 57, he was thrown out of a moving truck over the edge of a cliff, and appeared to have died in the fall.
Later, at his funeral, he appeared again, and explained that he had caught onto a tree limb, but broke his ribs and had to stay immobile for quite some time, as the pain of moving was too much for him to bear. While at the funeral, he noticed his father had not attended, neither had his son Rover, as the two were off searching for his body, believing him to still be alive.
- Indiana Jones and the Verge of Legend (Cameo appearance)
- Indiana Jones and the Kingdom of the Crystal Skull (First appearance)
- Indiana Jones and the Edge of Destruction
- Mutt Jones and the Trenches of Flame
- Mutt Jones and the Lost City of the Hovitos
- Mutt Jones and the Palace of Kings
- Mutt Jones and the Deserts of Storm
- Mutt Jones and the Rain of Fire
- Mutt Jones and the Sands of Desire