Thought Sienna was good in this
I have read no Hitchcock biographies and pretty much know the stories (or rumors) like most do but I was rather impressed by Sienna's acting here. She played the awkward tension between her and 'Hitch' rather well, you sort of strived for her, especially when she showed up with the black raven on her arm after her ordeal filming the horrendous attic scene over and over again.
I think I preferred this to 'Hitchcock' with Anthony Hopkins