Graham O'Brien's psychic paper

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The Thirteenth Doctor gave a piece of psychic paper to Graham O'Brien as a parting gift. When Graham and Ryan Sinclair learned about rumours of a troll invasion in Finland and gravel creatures in Korea they decided to eventually investigate that. Graham and Ryan were planning to use their psychic papers as they "[would] get [them] anywhere". (TV: Revolution of the Daleks)

Graham later attempted to use his psychic paper on Ace, but it only displayed the truth about his identity and his true thoughts, with Graham commenting that he "[couldn't] get the hang of this." (TV: The Power of the Doctor)