Thriller (also known as Boris Karloff's Thriller) is an American anthology television series that aired during the 1960–61 and 1961–62 seasons on NBC. The show featured host Boris Karloff introducing a mix of macabre horror tales and suspense thrillers.br br "Thriller (also known as Boris Karloff's Thriller) is an American anthology television series that aired during the 1960–61 and 1961–62 seasons on NBC. The show featured host Boris Karloff introducing a mix of macabre horror tales and suspense thrillers.