The specially trained agent Martin has been appointed to the most dangerous mission in Bulgaria - to go undercover in the gang of the mafia boss Djaro. On his way he has to encounter a lot of challenges in order to completely become part of the criminal world. His task becomes more complicated when he meets the big bosss girl Sunny. While undercover he gets a promotion in the mafia hierarchy and becomes part of the world - full of crime, violence and corruption. Undercover is a modern crime series which realistically depicts the reality of the underground world in Bulgaria. It is a fictional series and is not related to any real persons. However the plot contains a number of real events happening in the modern life that cover the pages of newspapers and magazines-gangster wars, drug market redistribution, forgery, gun shots in the city center, corruption schemes, bank robberies etc.