Instead it uses a special cartridge in which the bullet is pushed out by a propellant-driven piston. The piston is stopped by the neck of the cartridge, trapping the hot, noisy gas entirely within the chamber of the firearm. It is fair to say that Hollywood takes great artistic liberties with silencers. Most real designs are very much larger than the cigar-tube sized ones typically shown on film and usually much less simple to fit and remove. Despite what is shown in films, it is usually impossible to silence a revolver because the gap between the cylinder and the barrel allows gas to escape.
Real designs are more likely to produce a muffled crack, or to sound like a car door being slammed.