Dr. Maura Isles, is the Commonwealth of Massachusetts' Chief Medical Examiner and a forensic expert working at the Boston Police Department. She is Rizzoli's best friend. Maura is a walking library, able to spout out a litany of facts, regardless of whether or not they are relevant to a case. She has a pet tortoise named Bass, after renowned forensic pathologist William M. Bass. Maura is not easily ruffled and has a steady temperament. She absolutely loves examining dead bodies, but she has a tendency to diagnose living people a little too often. She is an adopted only child of a wealthy family. In high school, she was nicknamed "Maura-The-Bore-A" because her classmates thought she was boring. She is always dressed impeccably, as if she were going to a photo shoot. She is known around the force as "Queen of the Dead"; her ring tone on Jane's phone appropriately plays Chopin's "Funeral March". Maura is the complete opposite of Jane, though they are best friends; Rizzoli is more of a tomboy, while Maura always looks like she is going to a fashion shoot rather than to the morgue or a crime scene. Though Maura is socially awkward and has trouble with men due to her brutal honesty and habit of revealing all their medical conditions, she isn't awkward around Jane. She can analyze x-rays and blood chemistries, can slice open muscles and organs, but possesses no scalpel with which to dissect human emotions. Maura also can't lie; if she does, she starts to hyperventilate. It is later revealed that her biological father is an Irish crime boss named Paddy Doyle, something she finds out while investigating her half-brother's death.