A Scientist is convinced he is able to break The Sound Barrier and after much researching in his lab comes up with the answer. However after his son, the willing participant, dies it is left to the scientist's son-in-law to take the controls. The two then bond on a new level while breaking The Sound Barrier together.
Though a lot less romantic than the Chuck Yeager section of The Right Stuff, this clipped British account of the breaking of the sound barrier is an entirely fictionalised version of events the later film records fairly accurately. Rather than a drama of individual heroism, this is a story of stalwart teamwork, with boffin Richardson fooling around in the laboratory scratching his head and puffing on a pipe while his son-in-law, modest test pilot Patrick, replaces the scientist's dead son and climbs into the experimental plane to prove that the envelope can be expanded.
It's an interesting scientific-military soap opera, acted with stiff upper-lip restraint by a great cast, but Lean's visual sense really comes into play in the aerial sequences which go beyond scientific interest to suggest an existential exhilaration in sheer achievement.
Not being a real account on how The Sound Barrier was broken allows the writer to add new sub-plots like the relationship between the scientist and his son-in-law. With Niven at the helm the direction is reliably slick and engaging, with the aerial shots standing out in particular.