One of the biggest scenes of the Aussie flick will be shot in High and Andrew Streets from about 7pm tonight. Filming will continue on Tuesday night.

The Maitland-filmed scene will appear at the end of the movie.

Based on the popular John Marsden novel of the same name, the film focuses on Ellie and a group of friends who live in a country town in Australia.

While on a camping trip into a remote part of the countryside a foreign army invades.

When the teenagers return, their families and the entire town have been imprisoned and Ellie and her friends must decide whether to hide or fight.

Filming for the movie is expected to inject more than $20 million into the economy.

Australian screenwriter Stuart Beattie will make his directorial debut on the project, having previously written for the Pirates of the Caribbean trilogy.

“Maitland is definitely one of the hero locations for the film so there will be a lot of filming activity around the Maitland Local Government Area from the end of the month through to the middle of November,” Annette Hubber from Screen Hunter Central Coast said.

Neighbours’ star Caitlin Stasey has been cast as the lead Ellie Linton, Phoebe Tonkin will play Fiona Maxwell while Ashleigh Cummings will play Robyn Mathers.

The male leads in the movie will be Chris Pang as Lee, Deniz Akeniz as Homer Yanos, Andy Ryan as Chris Lang and Lincoln Lewis as Kevin Holmes.

Tomorrow, When The War Began will also be filmed in Dungog and Port Stephens.