Porter was assigned to the case of Spring-heeled Jack and spent many months tracking him across London. On one occasion, he was called to Covent Garden where Jack had been sighted. However, he escaped again. Porter berated Bates for scaring him off and then questioned the Eighth Doctor as he had reportedly caused a disturbance before Jack's arrival. However, Penny Chapman vouched for him. Arnold discussed Jack with the Doctor, promising him that he was a marked man.