Four ancient scholars take a road trip in the Southwest of the US, a journey that brings back their youthful adventures and explores the influence each of them had on the scientific elucidation of the secret world of the universe. The astronomers’ careers took place during the period of the 'space race' and so they have plenty of memories from a very distinct time period in the 20th century. From the discovery of space in the 60's to the Cold War and more recent discoveries.

Each of them has their own strength: Robert is the designer of instruments, Donald’s the theorist Donald, Nick is the visionary and Wal is the observer. Together, they represent the most productive period in the history of astronomy. They helped build the biggest observatories and made revolutionary discoveries about the universe, discoveries that influenced the image that humanity has of itself.

Together they go on a journey, from the ancient telescope at Mt Wilson to growing observatories. They redo a hike in the Grand Canyon that almost got the best of them as young men. During the journey through breathtaking scenery, they look back on their academic achievements, but also reflect on how their work had an impact on their own vision of life, on the question whether life has a purpose, whether there is a bigger picture and whether there will always be limits to our knowledge. 'Star Men' is not only a very personal documentary, but also a comprehensive film about the big life questions.