I have bad mouthed producer Joan Harrison's other hour long episodes, so must praise her this time. Like with the CONSIDER HER WAYS episode this is an unusual story for the series, unlike that episode this is well scripted. It does have a Twilight Zone like quality though it is better than most of the hour long Twilight Zones. And yes a particular Zone half-hour episode did kind of set the bar high for how this story resolves but that does not make this show unworthy, in fact it rivals that chilling ending. And this is based on an H.G.WELLS story that pre-dates Zone's IT'S A GOOD LIFE by a number of years anyway. Though the original story covers events in about the first half of this show, they extrapolate the rest in the adaptation.
Basic situation starting with trying to fulfill a child's birthday wishes leads into unreality and doubt keeps twisting and turning heading into places you don't expect. It's well acted and there are a few memorable flourishes from director Robert Stevenson. One involving a fire and another a crushed head. Music score is well done and was reused in other episodes. Only weak element here involves some off screen dog action that just comes off as cheap. In the original story the animal is a cat, just FYI. Naturally too the short story has more elaborate magic tricks than could be done when this show was produced. But what they do show here is effective most of the time.
There is some real horror here and a nice non-explanation explanation scene somewhat like the diner scene in THE BIRDS where the whys of the situation are left open but given some possible reasons and creating more genuine mystery to the whole thing.
This is ultimately a horror story with some horror in it and thought.