there are similarities between the bellatrix and helena?

I think Helena has a hint of an inner Bellatrix inside her, the crazy character she develops in Harry Potter shows a certain familiarity to herself becasue she plays Bellatrix so well. I think Helena being the versatile and amazing actor that she is, she has to have a part of every character she plays for the fact she plays them so well with a sense of প্রথমপাতা inside herself, which makes her a believable actor and therefore হারিয়ে গেছে in the movie.

Watch this video =) She says they have the same laugh (of course)! And they do look pretty much alike since Helena is Bellatrix...

I think YES..otherwise she would not played. Helena is "crazy" like Bellatrix XD.

They look the same XD

I think I heard somewhere she has one of the same personality disoarders as Bellatrix.

Helena's similarity to Bellatrix was her laugh

Not really because Helena doesn't see herself as sadistic and immoral... the one thing that they have in common is maybe their laugh...