Harrison's acting career started when he gained a place at drama school in 1979, but he has been fourth official at London Welsh, which involves overseeing substitutions, for the past five seasons. His acting credits include A Touch Of Frost, The Paradise Club, The Bill, The Green Green Grass, while his first job was playing Jesus.He said: "I love acting but I loved rugby at the same time, so it was very difficult. But acting paid the bills."