This animation by Dudok De Wit uses 'lyrical lines' and simply drawn characters, which express the landscape, as he has always been inspired by the 'clean line' (mainly from Herge's comic books). He states that the clean line 'seeks suggestion and meaning in its purity'.
He sees the layouts and visual compositions as movements. When he draws landscapes, he visualises the lines and shapes that show the directions and dynamics.
In an animated film, all these interesting movements; the moments created by dynamic lines in each landscape, by the animation of the characters, by the transitions from one landscape to another provide a poetic quality, that help to make the narrative clearer.
I particularly like how DDW. has used the same landscapes throughout the animation, which I think creates a consistencey and stresses a sense of time passing, strengthens the narrative.