Every time you sit back and rock with laughter at the efforts of 'The Office', 'The Royle Family', 'Arrested Development' and 'Modern Family', send a silent prayer to one man.
Because it was Christopher Guest - always Nigel Tufnel to many - who (arguably) pioneered this much-borrowed style of film, with his genre-changing efforts in original 'rockumentary' 'Spinal Tap' and the more recent 'Best in Show'.
To celebrate the DVD release of his BBC comedy 'Family Tree', out on 23 September, we take a look back at just some of Guest's best moments...
Christopher Guest's 'Family Tree' is out on DVD on Monday 23 September from Universal Pictures (UK).