Ira and the radio show staff get their results on the psychopath test from Dr. David Bernstein, of Forensic Consultants, LLC., who administered the test to them.

Host Ira Glass talks about the surprising way apologies tend to play out in couples when one person has cheated on the other, based on stories his mother, Dr. Shirley Glass, told in her book Not Just Friends. And contributing editor Sarah Vowell tells us about the time she couldn't stop apologizing.

Story of a romance that began in a mental hospital. Sometimes, the line between crazy and not crazy is blurry; certain behavior could mean either thing.

Ira explains that when the radio staff decided to take a test that reveals who is a psychopath, very quickly everyone came to believe that the highest score would go to either Robyn, Jane, or him.

Host Ira Glass plays tape of two women who ended up as frenemies.They kept trying to be friends, but couldn't help themselves from fighting. Ira then speaks with psychologist Julianne Holt-Lunstad who has run scientific studies to answer the question: Why don't we simply end these troubling kinds of friendships? Holt-Lunstad's research also shows that these relationships are much more common than you might think.