Ronald Harwood has signed on to write a movie about the final days of Russian Czar Nicholas II and his family, after they were captured by the Bolsheviks, exiled to Siberia and finally executed.

Harwood will base the film on Robert Alexander’s bestselling novel “The Kitchen Boy: A Novel of the Last Tsar,” which takes a fictionalized look at those last days before Nicholas II, wife Aleksandra and their five children were gunned down and buried, with so many jewels hidden in their clothing they provided some protection from the gunfire.

Glen Williamson, who most recently produced “Push” and the upcoming Amy Adams-Emily Blunt comedy “Sunshine Cleaning,” found independent backing to option the book and hire the writer.

Williamson’s company, Back Lot Pictures, has a first-look deal with Big Beach Films, but Williamson said he preferred to get a screenplay from Harwood before setting the film up with a distributor-financier.

Harwood most recently scripted “The Diving Bell and the Butterfly” and the Baz Luhrmann-directed “Australia.” His plays “Taking Sides” and “Collaboration” will open on the West End in May.