Batman: The Animated Series: 10 Best Characters Who Only Appeared In One Episode
1. Simon Trent/The Gray Ghost - Beware The Gray Ghost
"Beware the Gray Ghost" is such a tremendous episode of Batman: The Animated Series, brining multiple incarnations of Batman together, as 1966 Batman star Adam West voices Simon Trent. Trent is an actor known for playing the Gray Ghost, a costumed vigilante who was one of Batman's boyhood heroes.
When a series of bombings occurs in Gotham City, Batman notices the connection to one of the classic episodes of The Gray Ghost. Batman visits Trent for advice, where the Dark Knight tells the actor that he inspired him in his own vigilante crusade.
After a rough patch where Trent despised ever playing the character, he rediscovers his love for the Gray Ghost and dons the familiar costume once more. He assists Batman with the investigation, and eventually they catch the criminal behind the string of attacks.
It is brilliant to see the correlation between real life and animation, as Adam West both inspires Batman in this episode, and also served as inspiration for so many of the real-world actors to play the Caped Crusader.
The late actor's performance alongside Kevin Conroy is one of the biggest fan-service moments in the series, and the character's one appearance stands above all the other one-time guest stars.