Jodorowsky's Dune Uncovered
Scene 124-125 : Paul Conquers Shai-Hulud
Carrying out the order to kill all the Fremen, a Harkonnen transporter lands near a sietch and move towards it, suddenly Fremen emerge from beneath the sand, killing the Harkonnen and shooting down the transporter as it tries to escape.
Later in the large flat land Chani, holding their son, watches Paul as he listens to Stilgar.
Stilgar tell Paul that today he will call a worm and ride upon it. Paul kisses Chani and his son, and walks off towards a spice field, carrying two hooks and a thumper.
Paul activates the thumper and calls the largest worm ever seen. Chani exclaims the prophecy is being fulfilled, it is Shai-Hulud the white!
Paul sinks his hooks into a ring segment, and the worm turns over until Paul is on top of the worm, a true Fremen!
A few of the Moebius storyboards for these scenes are available that match the script, and Chani's exclamation is also very similar between the script and the storyboard.