Complex sentence: In April 2011 he was cast as Fili the Dwarf in Sir Peter Jackson's three-part film adaptation of "The Hobbit", which led to an advertisement for Air New Zealand, where he had a cameo appearance.
Split into simpler sentences: In April 2011 he was cast as Fili the Dwarf in Sir Peter Jackson's three-part film adaptation of "The Hobbit". Which led to an advertisement for Air New Zealand, giving a cameo appearance.