The Blue Lamp Reviews
This film starts about thirty minutes too early; it's over a third of exposition. What is more, there is clear thesis to the film as it basically states in the first minute that it lauds the efforts of British police, and the film doesn't blanch at showing their bravery, resourcefulness, and teamwork. The officers are not flawed characters, nor are they really characters with any dimension. The bad guys are bad, nothing exceptional. And the plot unfolds rather predictably.
Overall, I think this film might have been innovative in 1950, paving the way for The French Connection and other crime dramas, but today it doesn't hold as much sway.