Complex sentence: In July 2005 Bartlett took part in the Old Vic's "New Voices" 24 Hour Plays culminating in the performance of his play "Comfort" which had to be written and performed in 24 Hours.
Split into simpler sentences: In July 2005 Bartlett took part in the Old Vic's "New Voices" 24 Hour Plays. Leading to the performance of his play "Comfort" which had to be written and performed in 24 Hours.