Stupidity: The whole premise of the plan is summarized by Helen in the sentence "They don't know Andi is dead, so why would they suspect anything?" However, "they" conspired in unison to financially ruin her sister, and "they" did not answer the mail, none of them. The possibility that "they" all could have gathered and silenced her by force is one of the most likely ones, and yet neither she or Blanc consider even for a moment that the literal crime conspirators could have conspired.
Stupidity: Dr. April (as well as her patient Mrs. B) is nonchalant when her young nephew Zeke brings his dog hit by an automobile into the hospital. Dr. April, continuing to hold her clipboard, tells her nephew she is "not that kind of doctor" and "what you need is a doctor for animals." The doctor-aunt could have at least taken the dog from Zeke's arms to ease his panic and see if there is something obvious she could do to help the dog. Instead, she walks out with Zeke still carrying the dog. (00:02:45)