First, Mrs Harris came into the bathroom. Then/after that/next, she hid into the shower behind the curtain. When Mr Harris was brushing, she took the scale....

If I am a detective i can tell :

The woman was in her bedroom while his husband was in the bathroom. The woman put music in her bedroom because she had to practise for her concert(music) she couldn't hear any voices just the music ....
His husband decided to take his bath and this time was  the summer and he opened the window of the bathroom because it's was so hot  there. 
Suddenly he was brushing  his teeth one man come by window with a knife and wore  a black mask like a thief and he had a bate  ... This time was so awful because the man sought  to flee but it was impossible ... He souted but nobody  can hear his voice ...  Then the thief hit the bate in his head ...
When her wife have finished her praticse for the concert she noticed one thing very strange because his husband didn't come back of the bathroom so she decided to go and she saw her husband  died 

Voilà j'ai essayé dis moi si tu as des questions...