The new tool in the fight against crime is called "Smartwater" and its pretty slick.
The liquid is odorless and can’t be seen by the naked eye but it leaves a residue that lasts for weeks and glows bright green when under ultraviolet light.
Police say the material is almost impossible to wash off of clothes and will even last on skin for several weeks no matter how hard you try to wash it off.
Detective Inspector Madeline Ryder told The Daily Mail "the trap cars form part of an overall crime reduction strategy designed by SmartWater, which is an effective weapon in the armory of tools that we routinely use."
Cops in London are testing the system with dummy cars equipped with the ability to squirt the liquid.
The hope is that homes and vehicles in high risk areas can be equipped with the misting equipment and help in not only catching the thieves but in deterring crimes as well.