Emma Watson is after you!!!

Miss Watson has been signed to star in new period romance Napoleon and Betsy after Scarlett Johansson was seen to be too old for the part.

The 18-year-old Harry Potter actress will star as Betsy Balcombe, a headstrong young noblewoman who falls in the love with exiled Napoleon Bonaparte during his exile on the remote isle of St Helena.

Scarlett was set to take the role in writer-director Benjamin Ross' feature, but will instead be a producer on the project, alongside Alexandra Milchan, Melanie Sloan and Gilles Arondeau, according to the Hollywood Reporter.

It is thought that Emma will commence shooting on Napoleon and Betsy in autumn 2009 once filming of Harry Potter and the Deathly Hallows, the final instalment in JK Rowling's series of novels about the boy who lived is completed.

Having starred in all five Harry Potter films thus far produced, Watson is currently filming the sixth movie, Harry Potter and the Half Blood Prince, before working on the two pictures allocated to taking the Deathly Hallows to the big screen.

Watson, who turned 18 last week, was permitted access to the £10.5 million fortune she has earned while starring in the Harry Potter franchise but was instructed on how to manage her finances on a course organised by Coutts, the Queen's bankers.