Scrooge McDuck is telling his nephews about their many adventures, like when they found the lost Crown of Genghis Khan. Huey, Dewey, and Louie see if there is anything about the crown in the Junior Woodchucks' Guidebook. When they find out that Genghis Khan's grandson, Kublai Khan, took all the Mongol Empire's treasures to India, Scrooge becomes so excited he doubles his donation to Junior Woodchucks; nothing.
Then he go with Donald and the triplets to Asia to find the treasure of Kublai Khan. They go to Scrooge's old yak company, where a man is telling them to go to some mountains, if they want to find the treasure. So the ducks go there, and find a cave. In the cave is the river Alph, that leads to Xanadu, where the treasure should be. In the end of the cave, there is a sluice gate to the river. On the other site of the river, there was a doorway, that should lead to Xanadu. But they couldn't get to it because of the river. Huey, Dewey and Louie find out they just have to close the sluice gate, so the water stop running. Then, they cross the river and go through the door. The door locks behind them. Walking towards the legend city, they feel as if they've been there before.This is confirmed by a case they find. It is a case with Scrooge's medicine, so they realise that Xanadu is no other than Tralla La!
The locals welcome them despite of the trouble they caused the previous time and lead them to their master, Lah Deedah. The master shows no interest in the crown and invites them to live in the paradise of Tralla La. The ducks gladly accept the invitation to live carefree away from civilization. Even Scrooge forgets money and lives in peace.
A week later, Lah Deedah narattes a story to them over a cup of tea. It is about the dark times of Xanadu, when the Mongol emperor took over the happy valley. On his way out, Kublai Khan built a trap to the treasure he left behind: the dam. When the dam's gate closes, the valley floods. The ducks realize that they didn't reopen the gate and so they brought disaster to Tralla La once more. The locals realize that the river's vortex is no more. The ducks find a way to open Xanadu's door to close the dam's gate.They ask for Lah Deedah's help.
He leads them to Lama Tsamjah Phee. They ask him for metal to make saws and he gives them tons of steel bottlecaps. This is not the treasure Scrooge longs for. They melt the caps and make the saws.
The water level has risen so the use a canoe to go to the door. Donald is chosen as the biggest and strongest to open the door and close the dam's gate. He gets the job done but breaks the mechanism of the dam's gate. So the only road to Tralla La is premmanetly closed. The water's vortex brings the canoe to Donald, but throws the crown to the water to the water. The ducks try in vain to return to the surface. The river takes them even deaper. Hours later the canoe overturns and they are struggling in the water until they are carried to India, where their andventure ends.
Back in Xanadu, a farmer finds the crown and delivers it to master Dah. Lah Deedah, angry for the loss of the heroic ducks, throws the crown into the sacred vortex where it sinks to the rest of the legendary treasure of Kublai Khan.
Return to Xanadu was written and drawn by Don Rosa. It was first released in 1991.
Return to Xanadu is one of the few stories where Scrooge McDuck doesn't find the treasure he's looking for and at the same time loses another one he found previously. What he has gained is another adventure and a lesson for life. We see his greed softening. He's not sad for losing something valuable. This adventure reminds him of his poor but happy childhood in Scottland.