This excellent period piece carries the weight of its time very well: the political paranoid of the late 60s, the impersonal sinisterness of large corporation, and the general mood of exploitation and distrust in the air. Boorman is sophisticated enough a director to spice up the simple, noirish story with creative cutting and a wild soundtrack, which jogs our mind from time to time, leading us to suspect undetected depth in the movie. The search may be futile, but the attempt can be fun.
The movie was re-made in 1990s into a Mel Gibson vehicle, "Payback". While the movie is trash, it is nevertheless interesting to compare the huffy threat of Lee Marvin with the blatant madness of Gibson. Suffice it to say that each serves the movie they are cast in well, in their own way.