When a woman is imprisoned by a crazed vivisectionist, she must win the trust of the hybrids in order to escape and save her friends.

A great improvement on the original, thank you. Not really the plot I had in mind, but lots of possibilities. I may have to give you a credit...

Are the hybrids alive? Are the work of the vivisectionist?

Don't take the 25 word rule of thumb as a must because while less words are better, a word count is not essential. This is especially true if you are using the logline to help structure a plot instead of pitch an idea.

FFF is right "...a woman..." is too generic a description for a logline what is her unique character flaw that will make it harder for her to achieve her goal? Use one or two words to describe this.

Secondly the premise requires a leap of logic from the reader in order to make sense. Best to specify that this surgeon has many surgically altered animals or animal/human hybrids trapped with the woman. These are basically going to be the allies if they are essential to the plot mention them if not don't.

How about:
After being trapped with a group of animal and human hybrids by a crazy vivisectionist an obsessive compulsive accountant must gain the other inmates trust in order to escape and save their lives.

Hope this helps.