But what is it about the famous ship that makes the story so enduring and why does it still intrigue and touch so many people?
Digital Spy caught up with the cast - including Steve Waddington, Celia Imrie, Geraldine Somerville, Toby Jones, David Calder, Glen Blackhall, Maria Doyle Kennedy and Ruth Bradley - to find out why they think the tale of the Titanic is still as important today 100 years on from the boat's sinking.
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Titanic airs on Sunday nights at 9pm on ITV1.
Photo gallery - cast and set shots from Titanic: