Status Updates From Sick to Death

There are a fair amount of cliches in this book, enough to ruin an otherwise clever premise. I don't love where this is headed. Also, it's extra-unrealistic. There are a rash of public murders by this point, something like twenty (I forget the count) and no one has put any of the three at even two crime scenes? Also, the cyanide poisoning seems, well, unlikely to go unnoticed by the victims...