Nineties (Czech: Devadesátky) is a Czech crime television series that serves as a prequel to Případy 1. oddělení. The series is based on real criminal cases investigated by Czech Police. Main characters are based on real life investigators and other people. The cases reflect some of the most famous real criminal cases of the modern Czech Republic (Ivan Jonák, Orlík killers). Nineties became most watched Czech TV series since 2004 with average viewership of 2.23 millions viewers older 15 years and with an average audience share of 47.51%.