This paper reports the experiences of teachers involved in a novel retraining scheme designed to meet a short-term crisis in numbers of teachers of physics. Teachers trained in other subject areas underwent an intensive six-month training in physics and were then placed in schools. During the first year of teaching some support for ongoing learning in science was provided. A study of these teachers' experiences found they lacked content knowledge in areas of the curriculum other than physics and were unprepared for the reality of the science classroom. Their existing classroom management skills were of only limited value in the new context. For those graduates who were supported by experienced staff in schools, the transition to science teaching was hard but ultimately worthwhile. For some, whose qualifications to teach science were never accepted by their peers, retraining was a bitter experience.