Complex sentence: The company has evolved into a television and film production company, originally as Semtex TV Productions which produced the concert television special' in 2006 which was aired on NBC in the United States and Channel 4 in the UK.
Split into simpler sentences: The company has evolved into a television and film production company, originally as Semtex TV Productions. Its first production was the concert television special' in 2006, which was aired on NBC in the United States and Channel 4 in the UK.