Conflict
The conflict in The Hitchhikers Guide to the Galaxy is arguably the destruction of earth and Arthur's struggle to keep himself intact mentally as they go through space getting into trouble.
The main conflict in The Restaurant at the End of the Universe is trouble the group is having fighting off the vogons which spins them into great peril and causes a entire chain of events directing them to the ruler of the universe.
The main conflict in The Restaurant at the End of the Universe is trouble the group is having fighting off the vogons which spins them into great peril and causes a entire chain of events directing them to the ruler of the universe.