The ending scenes were quite satisfying but there is little to no character development. There are over 15 characters that are introduced in a 30-minute time frame, and the plotline is so weak.
For example
If Marta could lie without puking
If Ransom didn't make Fran call him "Hugh"
If Ransom's name wasn't Hugh
If Fran didn't have a backup toxicology report in the weed stash
If Fran died instantly
If "Hugh" didn't sound like "You"
If the dog didn't fetch the piece of the ladder
The story would just fall apart, the story is only as good as its weakest links, and this story has some weak links.
Also, how would the detective know that Morphine and the other drug had slight inconsistencies in viscosity, the chance that Marta could sense those small differences is truly overblown.