[4] In March 2020, mystery investigation program Cuarto Milenio became notorious due to a series of episodes broadcast in February, dedicated to the then incipient COVID-19 pandemic, in which several boards of guest experts accurately predicted the national impact that it would go on to have.
[8] Media impact in Spain was such that, when Cuarto Milenio put its broadcast on hiatus due to the situation, its director Iker Jiménez had to dispel rumors of political censorship exerted by the Spanish government, whose management of the pandemic had been strongly criticized in the program.
[12] On 22 October it changed its name to Horizonte: Informe Covid,[14][15] achieving that night its maximum ratings thanks to a video interview, the first in continental Europe,[16] with controversial Chinese virologost Li-Meng Yan.
[17] Started 2021, from a special episode on 7 January onwards, the program stopped focusing solely on the pandemic and spread its range to other fields of science and politics, including a reportage about big data and media manipulation in social platforms.
[3] The program was moved from Telecinco to Cuatro next week, shortening its title to Horizonte and making Informe Covid a segment, and made its debut in the new channel with a live analysis of the inauguration of Joe Biden in United States.