Heikki Johannes Silvennoinen was a Finnish guitarist, singer, songwriter and actor. Silvennoinen began his career with the rock band Tabula Rasa in 1972 but became widely known for the sketch series Kummeli, which began in 1991. Silvennoinen was one of the founding members and worked in the series as both an actor and a scriptwriter. From 2018 to 2023, he worked as a scriptwriter and second lead actor in the police comedy series Kontio & Parmas. Silvennoinen played in the Tabula Rasa from 1972 to 1977, which was one of the best-known representatives of progressive rock in Finland. Although Silvennoinen had been a driving force behind Tabula Rasa, he was more interested in blues-based rock, which he began playing in the 1980s in the bands Frendz, Catwalk and Q.Stone. In the early 1990s Silvennoinen released his first solo album. In the early 2000s, Silvennoinen formed the Finnish blues supergroup SF-Blues as a joint project between Pepe Ahlqvist and Dave Lindholm.