The first few minutes and the last few minutes of Metro are its worst. They both show Eddie Murphy indulging in inane humour that seems completely incongruous. Other than that, it's a fairly decent action flick and a reasonable timekiller.
Eddie Murphy is Scott Roper, a hostage negotiator in the San Fransisco Police Department. He risks his own life to save those people who are being held hostage by psycopathic criminals. During the course of his work, he runs into Michael Korda (Michael Wincott) who is smarter, colder, and crueller than anyone Roper has encountered before. This leads into a high-speed chase down the streets of San Fransisco (the hilly terrain of the city is highly amenable for the sorts of situations shown in the movie). That chase alone, even though a bit long, makes this movie worth watching. The rest of the movie has some slight twists to it, but it has all been done before.
There are a lot of issues that are raised in the movie that appear to be sub-plots, but nothing ever gets done with them, and Metro might be a first in teasing the audience with the hint of something deeper than the surface plot, but never realising it. Eddie Murphy's humour at times works quite well, especially in the way he interacts with his British girlfriend (Carmen Ejogo). I think both Wincott and Ejogo show promise for the future, but Murphy can do better. Metro is worth the matinee fare.