The NINJA clinical trial aims to compare two emerging schedules of radiotherapy in the treatment of intermediate or high risk prostate cancer. Participants will be randomly assigned to one of two radiotherapy schedules as part of this study. In schedule 1 (called Stereotactic Body Radiotherapy) participants will receive 5 radiotherapy treatments over 2 weeks, and in schedule 2, (called Virtual High Dose Rate Boost), participants will receive Stereotactic Body Radiotherapy delivered in 2 treatments over 1 week followed by 12 treatments of conventional external beam radiotherapy over 2 and a half weeks. It is hoped this research will potentially improve the accuracy and quality of radiotherapy treatment in prostate cancer.