The crooks in London know how it works. No one carries guns and no one resists the police. Then a new gang appears that go one better. They dress as police and steal from the crooks. This upset's the natural order of the police/criminal relationship and the police and the crooks join forces to catch the IPOs (Impersonating Police Officers), including an armored car robbery in which the police must help the gangs to set a trap.
When an alien hunter arrives on post-apocalypse Earth, it takes down a gang of warlords and unexpectedly becomes a folk hero to the oppressed locals. Now with their support, the alien sets its sights on the warlords' ruthless leader.
