There is an old Humphrey Bogart movie (I don't remember the title of the
movie just now although I have seen it a bunch of times before) and
Humphrey plays the part of a bad guy in the movie and they are going to
steal the payroll from a gas plant.One of the crooks buys a tractor
tanker (sort of like an 18 wheeler) and a guy who is playing the part of
one of the crooks,but is really a copper,installs a radio tracking
device underneath the tanker so the coppers can trace the truck
tanker.It is a real good old Humphrey Bogart movie.
cuhulin