Ridley Scott’s 'Gladiator' was a blockbuster that famously combined practical sets with digital 'extensions.' To recreate the Roman Colosseum, the production built only the first tier of the arena in Malta. The rest was added in post-production. To fill the stadium with 30,000 spectators, the effects team used 'crowd replication' technology, filming a small group of extras in different costumes and then digitally duplicating them. This allowed for massive, epic scale without the impossible cost of hiring tens of thousands of real people. The film won 5 Oscars and proved that CGI was now capable of recreating history with a level of realism that looked entirely photographic.