This paper is an account of the intensive psychotherapy of a young girl on the autistic spectrum. It describes her confusing presentation and how this suggested a tendency to oscillate between mainly unintegrated states of mind. Important themes that emerged included the phantasy of inhabiting a claustrum; the use of adhesive identification to defend against the bodily felt terror of separation; and fear of damage to the maternal object. The paper also discusses the trans-generational aspects of her difficulties and considers how her therapy helped growth to take place.