Entertainment factory Film- und Fernsehproduktions GmbH (ef for short) is the production company of the popular ARD TV series “Hubert ohne Staller” (under this title since 2019; previously from 2011 to 2015 Heiter bis tödlich: Hubert und Staller and from 2016 to 2018 Hubert und Staller), which has an average audience of 2.422 million viewers. (Source: crewunited.com)