When planet earth is destroyed, a comfortable, miserable and lonely man must hitchhike through space and learn to leave his comfort zone and enjoy life.

I would suggest dramatizing the plot with the outer journey main beats rather than describing only the inner journey.

After the destruction of planet Earth is approved by the local space council a tea swilling introvert English man must hitchhike his way across the galaxy to divert the construction of an intergalactic highway away from Earth to save man kind.

Hope this helps.