Richard Attenborough may be listed first in the credits for this drama, but I feel Bernard Lee gives a more impactful portrayal as the shop steward "Bert." He urges the workers at an engineering plant to begin an unauthorized strike; most of them participate, and it doesn’t take long for viewers to realize that someone within the workforce is trying to exploit the disagreement to further their own aims. We also meet some local toughs who don't hesitate – sometimes resorting to violence – when dealing with those few workers who ignore the picket line and keep working. "Curtis" (Attenborough) is one of these men; he’s already a father to a young son, and his wife is pregnant again, so he can’t afford to lose his income. He quickly becomes the target of resentment from former coworkers as they completely reject him. Director Bryan Forbes and Michael Craig ("Wallace") also contributed to the screenplay, which results in a palpable feeling of threat as those who defy the strike find their safety and possessions at risk while their previous friends grapple with guilt. Brian Bedford is memorable as the brutish "Barrett," and Pier Angeli provides a noteworthy, though limited, performance as the young man's wife, "Anna." Typically, one would assume this narrative would focus on an employer’s misuse of authority; however, here it's evident that those abuses are stemming from individuals with wider ambitions who can easily sway a workforce like political followers. The conclusion feels hurried—almost unfinished, regrettably—but the cast and the subject matter work exceptionally well together to produce a film that provokes reflection and manages to convey a great deal within ninety minutes.

Source on TMDB