ITV confirmed that it had greenlit production on the programme last month. It has been written by Oscar-winning, Downton Abbey scribe Julian Fellowes.
Titanic is being produced as a 2x90 minute and 4x60 minute miniseries. It will begin filming in Hungary from the end of April ahead of broadcast - which will coincide with the 100th anniversary of the ship's sinking in 2012.
Linus Roache, who recently appeared in Coronation Street alongside his father Bill Roache, and Geraldine Somerville, who has portrayed Lily Potter in the Harry Potter series, will be joined by performers including Celia Imrie, Toby Jones, Perdita Weeks, Lee Ross, Jenna-Louise Coleman and Sophie Winkleman.
Also among the ensemble cast will be Stephen Waddington, David Calder, James Wilby, Antonio Margo, Dragos Bucur, Stephen Cambell Moore, Noah Reid, Lyndsey Marshal, Mark Lewis Jones, Ruth Bradley, Peter McDonald and Sylvestrale Touzel.
As previously revealed, Titanic will focus on different characters ranging from steerage passengers to upper class guests as their journeys come together in the ship's final hours.
Laura Mackie, director of ITV drama said: "Following the hugely successful Downton Abbey, Julian Fellowes has delivered another compellingly written and ambitious drama for ITV1. Coupled with exceptional homegrown talent both on and off screen, Titanic promises to be the must-see original drama for this landmark anniversary."
Creator and producer Nigel Stafford Clark of Deep Indigo Productions added: "There is a lasting fascination with the Titanic's one and only voyage, and never more so than in the year of its hundredth anniversary. We will tell the story in a way that is bold, fresh and gripping, with all the human detail that television does so well. We hope it will be a fitting tribute to the events of that night."
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