What if you lived your whole life without i-Pods, phones, TVs, Blackberries or even a radio? What if the light in your underground world was failing? This is the reality for teens Lina (Saoirse Ronan) and Doon (Harry Treadaway) in the new sci-fi adventure City of Ember.

Lina (Saoirse Ronan) and Doon (Harry Treadaway) hide from an evil henchman Credit: Fox Walden

Story, based upon the popular novel by Jeanne Duprau, goes..... for over 200 years the underground city of Ember has sustained the lives of its inhabitants and a giant hydro-electric generator has kept the lights on. Now, the city is wearing out and blackouts are happening more and more. Teen Lina, who has just been assigned the lifetime job of messenger, and her friend Doon, who is working in the massive pipeworks in the hope of getting to the bottom of the blackouts, learn the truth, despite the denials of city officials and other adults. Will they follow in their parents' footsteps and seek the fabled exit to the surface world?

Not having read the novel, I wasn't sure what catastrophe drove the inhabitants of our world to preserve Mankind in an underground city for 200 years but I assume either a nuclear disaster or a planet-wide environmental holocaust. Either way, the citizens of Ember have been chugging along for a bit longer than the "builders" intended unaware of a surface world. Whether or not this film is a cautionary tale, it is very effective and hey, it's just fun! It will entertain you with the massive sets, fast action sequences and interesting characters and it will also make you think..."what would I do?"