NCIS: Naval Criminal Investigative Service Episode 4.22 In the Dark

After a blind photographer discovers that he'd photographed a dead man deserted in an alley, the blind man's memory and photographs of the scene become NCIS's only leads in the case. Using these tools, the team is able to trace the murder back to a co-worker of the victim, who himself was under investigation for embezzling funds. But after the co-worker is found dead with a suicide note confessing that he and the victim had been running an embezzlement con, and that he'd murdered the victim when they had a falling out, Gibbs' gut tells him the note was coerced. Gibb's skepticism is proven correct after a particularly astute observation by the blind photographer, and a cryptic message left in the suicide note, lead to the true killer.