- Rod Serling: It's been said that science fiction and fantasy are two different things: science fiction, the improbable made possible; fantasy, the impossible made probable. What would you have if you put these two different things together? Well, you'd have an old man named Ben who knows a lot of tricks most people don't know and a little girl named Jenny who loves him - and a journey into The Twilight Zone.
In a park, a group of little kids play with Old Ben (J. Pat O'Malley), an old man with various abilities like super strength and shape-shifting. The children don't find this strange; they just consider him fun to play with. They go for baseball, but Ben knocks the ball to the horizon when it's his turn to bat. Disappointed, they ask him to transform into a hideous alien that they can pretend to fight, so he complies.
It's getting late, so everyone goes home. Ben carries Jenny (Susan Gordan), who wears a leg brace, to her apartment. Jenny's bitchy, shrewish guardian, Mrs. Gann (Nancy Kulp), orders Jenny inside and is very rude to Ben. He bids Jenny goodbye and leaves.
Later, two men in suits roam the block asking people if they have seen Old Ben. Mrs. Gann assumes they are cops and is eager to assist them, as she cannot stand things out of the ordinary like Old Ben.
Old Ben sneaks into Jenny's room. He explains that he is an alien criminal who fled his planet and took refuge on Earth and that the two men are officers from his planet sent to arrest him. Old Ben says sadly that he must flee once again. As a parting gift, he heals Jenny's leg with a device. He admits that he was tempted to do that the moment they met, but the alien cops would have detected it and tracked him down. He leaves, with Jenny tearfully begging him not to go.
The two men track the energy signal to Jenny's apartment. After seeing Jenny can now walk, they deduce what Ben has done. One of them points a device at Jenny. The other is horrified and asks if he's gone mad, but he retorts that they don't have many options at this point. He zaps Jenny and she collapses in pain.
Later, a doctor makes a house call and examines Jenny. Mrs. Gann asks what happened to her. The doctor sadly admits that he can't figure out what's wrong with her and leaves the room. Mrs. Gann follows him.
Old Ben returns and heals Jenny, but their reunion is short-lived when the two men enter. Ben angrily tells them that harming Jenny was uncalled for. They apologize, but claim that they needed the chance to find him. It is revealed that Ben is not a criminal; he is the beloved monarch of the alien planet. He grew weary of his responsibility and fled. The two men were sent to find him and plead with him to return, as their people love him and are lost without his guidance.
Ben reluctantly agrees to return, but when Jenny requests to come with him, they refuse, saying it is against the rules. Jenny gets an idea and asks for one minute alone to say goodbye to him. They agree after Ben promises in the name of their ancestors not to run away. The men leave the room, and it is revealed that they apparently froze time to prevent interference. They consider Mrs. Gann, then pull her cigarette out of her mouth and dispose of it.
The men return to find that Ben has shape-shifted into Jenny! They are unable to tell them apart and are forced to take both.
- Rod Serling: Mrs. Gann will be in for a big surprise when she finds this (holds up a photo of a handsome young man) under Jenny's pillow, because Mrs. Gann has more temper than imagination. She'll never dream that this is a picture of Old Ben as he really looks, and it will never occur to her that eventually her niece will grow up to be an honest-to-goodness queen - somewhere in The Twilight Zone.
- Adult Fear: Imagine being a guardian (even an abusive one) of your orphaned niece and finding her sprawled out unconscious and gravely ill. Now imagine that when you call up a doctor, said-doctor tells you there's nothing he can do.
- Always Save the Girl: Ben intended this when he returned to heal Jenny. It becomes in inversion when it's revealed he has to return to rule, because his people need him.
- Anger Born of Worry: Mrs. Gann has shades of this when Jenny falls ill for seemingly no reason.
- Batman Gambit: The two men make Jenny sick because they know Ben will return to heal her. This gets lampshaded.
- Even Evil Has Standards: Before we know who the two other men are, the reaction of the one who protests making Jenny sick comes off as this. By the end of the episode, it's more like "Even Desperate Has Standards".
- Everyone Has Standards: Even though Ben is cross at Ms. Gann's abusive treatment towards Jenny, he is wise enough to advise Jenny not to hold a grudge against her aunt.
- Fantasy-Forbidding Father: Ms. Gann shows hints of this during this exchange with Jenny:Ms. Gann: Who were you talking to?Jenny: Myself.Ms. Gann: Cut it out. You can go crazy that way.
- Freudian Excuse: Played with. While not specified, Ben theorizes that perhaps Ms. Gann and her abusive temper are a by-product of how she was brought up.
- I Did What I Had to Do: Essentially the other man's justification for hurting Jenny.
- Mandatory Unretirement: Ben is forced back to being king because no one else knows what to do, seemingly.
- MayflyDecember Romance: According to the ending narration, this will happen with Ben and Jenny. He's a centurion alien king, and she's a human girl. He can heal her, though, so maybe he can slow down her aging...
- Mundane Utility: Ben uses his shape shifting powers to play with the children.
- No Indoor Voice: Ms. Gann, mostly when she's scolding Jenny and telling off Ben to stay away from her niece. Even Ben makes a point that her loud volume is unnecessary.
- Pet the Dog: Although her aunt is a nervous and abusive guardian, when Jenny falls gravely ill, her aunt is nice enough to tuck in the bed covers for her niece.
- Screw This, I'm Outta Here!: Ben did this after a few hundred years of ruling his planet.
- Shape Shifter Default Form: We see both Type A (the photograph) and Type B (his appearance for the rest of the episode).
- Sincerity Mode: Jenny says Ben must have been a really good king if the two men were searching for him that badly. The men agree with her, saying Ben was their best king.
- Something Completely Different: Downplayed; this is the only other time Rod Serling has appeared on screen for the closing narration.
- Spot the Imposter: The men are unable to figure out which Jenny is the real one, so they take both Jenny and Ben with them.
- Voluntary Shapeshifting: Ben can change his shape into anything he can imagine.
- Would Hurt a Child: The two men make Jenny ill so that Ben will return to heal her.