They could also be the basis of one of those composer biopics that Hollywood used to make, with titles like "Song of Love" and "Song to Remember." There's the story itself, plus an interesting cast of supporting characters: composers, royalty, even P. T Barnum, who brought Jenny Lind to America. Any ideas on casting? Who could play Mendelssohn himself? (I've penciled in a couple of names already.)
Felix Mendelssohn: ???
Jenny Lind: Scarlett Johansson? Kate Winslet?
Queen Victoria: Keira Knightley
P. T. Barnum: John Goodman
For a title--what about "Song Without Words"?
I dunno - the first actor that came to mind was Adrian Brody...but the portrait accompanying the linked article sure looks like Alan Cumming. Adrian Brody wins.
Or, you could do the sibling-casting thing and do John and Joan Cusack as Felix and Fanny. He plays tortured pretty well.
It came to me over the weekend: Jude Law as Felix.