Extreme Bodies profiles conjoined twins Lori and George Schappell who are joined at the skull and partially share a brain. Scientists use MRI machines to determine that they do not share thoughts. It then examines the case of Krista and Tatiana Hogan who are joined at the head, but also seems to share a mental activity. Finally, the surgery examines the delicate operation to separate infants Erin and Jade Buckles who are conjoined at the chest.