A 32-year-old man presented with a four year history of reduced libido, erectile dysfunction and inability to conceive with his partner. He went through puberty normally and had a normal sense of smell. Clinical examination revealed that he was 205 cm tall and normally virilised. Testicular volume was reduced, but the phallus was normal. Clinically, he appeared euthyroid and there were no features of hypercortisolism or growth hormone excess. Biochemical picture: prolactin 375 (nr<350 mU/l), testosterone 15.9 (1028 nmol/l), follicle stimulating hormone 39.0 (<12.0 U/l) and luteinising hormone 23.6 (<9.0 U/l). Pituitary MRI revealed an enlarged pituitary gland (14×11×10 mm) extending into the suprasellar cistern with minimal optic chiasmal compression. Perimetry revealed a normal left visual field and 2 spots missing in the periphery of the right visual field. Karyotyping revealed 47,XYY. Ultrasound testes showed a 1.5 cm focal rounded area of ill-defined abnormality for which he underwent left testicular orchidectomy and right testicular biopsy. Histology revealed Sertoli cell-only syndrome. The pituitary surgical opinion was to observe with annual MRI pituitary scans and visual field examinations. The patient was treated with Cabergoline and Tadalafil. He was referred to the fertility clinic where his partner underwent donor insemination and delivered a healthy baby. The enlarged pituitary in our patient seems to be on account of pituitary gland hyperplasia with macroadenoma being a differential. Sertoli cell-only syndrome is a rare cause of infertility and should be considered in men aged 2040 years with a normal karyotype. However, in our patient, the karyotype was abnormal (47,XYY), which is another cause of infertility. Our rare and complex case highlights the importance of considering more than one cause of infertility and the need to involve a multidisciplinary team (endocrinologist, pituitary surgeon, andrologist, histopathologist, geneticist, ophthalmologist) to unmask the diagnostic web.