Patrick Stewart never ceases to be amazed by the healing powers of Star Trek, particularly when fans write to thank him for helping them through difficult times.
One fan letter in particular left Stewart - who played Captain Jean-Luc Picard in the show and movie spin-offs - almost moved to tears.
He recalls: "(The letter) was from a Las Vegas police sergeant, he wasn't asking for anything, he just wrote and said how much the show meant to him, and that he loved his work but there were many times when it made him very low and very despairing about society.
"He said: 'When that happens, I go home and watch The Next Generation and it restores my belief that it will get better."
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