Goofs

There are no marks on Brooke's neck minutes after she's strangled by the cord.

Tiffany consumed brewer's yeast to lessen the effects of the wine. In a July 2014 study by National Public Radio, brewer's yeast had no tangible effect upon the blood alcohol content of the test subjects beyond that of ordinary food. It was classified as an urban legend.

Tiffany shows up when Jackie meets her former husband Greg. She had not been following Jackie, so would not know where to find them. If she had not showed up, Greg would not have died, which was a significant plot event.