Redundant and unnecessary.

Blistering performances.

An old-fashioned movie made with new-fashioned finesse.

The movie turns out to be a little better than the average. Starting from a romantic formula often seen in the cinema, it ends in the most predictable (and somewhat bland) way.

This is a film which I can never remember seeing on TV.Unfortunately it seems as relevant today as when it was made as there have been terrorist campaigns since and sadly at this present time.However what is so ironic about this film is that people were lead ,wrongly to believe,that the security services were on top of the situation,whereas Burgess,MacLean and Ogilvy were happily giving secrets away to the Soviets.Of course they couldn't be guilty,they went to Oxbridge.The film is extremely well written and directed.

After a big explosion in the London Docks, Scotland Yard and MI5 join forces to find the ones responsible. Meanwhile the bombers, a group of communists, set their eyes on a much larger target, several power stations around the country, including London's Battersea power station. The group have enlisted a weakling shop seller as one of their helpers, but he slowly starts to crumble and fall apart. Meanwhile the investigators go over each lead and are slowly able to identify members of the group. But they don't know when the next attack will be or where.A Cold War thriller that starts with a bang and ends with a big finale inside Battersea power station. By shifting the focus back and forth between the investigators and the Communist group (which is never mentioned directly, but strongly implied), including the moments where their paths cross, the movie maintains tension and suspense. The cast isn't too well-known but contains a ton of familiar British character actors, from the lead detectives, Liam Redmond ('Night of the Demon') and André Morell ('The Bridge on the River Kwai') to the leader of the group, John Bailey ('Never Let Go') to Geoffrey Keen (Sir Frederick Gray in half a dozen James Bond movies) and so on.Directed and co-written by Roy Boulting, one half of the Boulting brothers ('Brighton Rock', 'Seven Days to Noon'), and with future acclaimed cinematographer Gilbert Taylor behind the camera ('Star Wars', 'Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb'), this movie is expertly made. It's got a nice pace to it, and by mixing interior studio sets and exterior on-location shots in London, as well as inside Battersea power station, the movie also looks pretty nice. It's not a classic by any means, but hard to go wrong with this one.

A really splendid Cold War thriller full of good London location shots showing scenes in the capital that have sadly gone forever.There are no star names,just first rate character players some of whom no British films are complete without. Special mention should be made of the Irish actor Liam Redmond who wonderfully underplays his role as the Commander with his dry wit and quizzical smile.To me, this is possibly his best film. It seems such a great shame that this film is seldom (if ever) shown on Britsh TV. I came across it in a second hand shop issued as part of a British Classics video collection. It's a great pity that this superb picture is not more well known.

I agree with the writer of the previous comments. This is a little gem of a thriller, not because it has unusual plot twists, or even especially good acting, but because of its fantastic pacing (more like a modern thriller than the usual fare from 1951), and because of its fabulous shot-on-location scenes that put you right in post-war London. I grew up in post- war Britain, so perhaps I'm biased; but some of my favourite films are those which manage to escape the confines of the studio, something that was much rarer in those days than it is now. The world of the film is now more than half a century distant, and when you watch those streets, buses, and cars, those people walking around, it's slightly shocking to realize that many of them now sleep the big sleep, that you're looking through a window into the past. This alone, for me, is worth the price of admission.The film is also the least talked about, most neglected of all Boulting's films, and as far as I can make out, hasn't ever been released on VHS, let alone on DVD, probably because, once the 1960s New Left had come into the ascendancy, especially in the various film studies institutes, the kind of old fashioned Cold War politics Boulting's film embodies were seen as both embarrassing and naive. Well, it's time for a re-evaluation. The politics of the film never did make much sense, so what we're left with is an exciting, well-crafted, and beautifully paced thriller, one that has, perhaps surprisingly, more heft than many contemporary thrillers, certainly more pizazz than the usual James Bond entries. If you can see it (and I discovered it courtesy of A&E, who ran it as a kind of joke several times in the early 1980s) sit back and enjoy it.