But "To the Chicago Abyss" earns it from me. Primarily because it lives up to the title of the show. It's Ray Bradbury through and through. Not every episode of the series lived up to the prose of Bradbury. Some just weren't suited to TV, some were too interested in trying to overcome the limitation of the practically non-existence budget, and some of Bradbury's short stories just didn't make much sense. At least to me: your mileage may vary.
But when Bradbury was clicking on all cylinders, he clicks. There are other episodes, like "The Pedestrian", where you're listening to Bradbury's poetry. "Abyss" is another. I've never been substantially impressed with Harold Gould, but he hits it out of the park here which is basically him standing there and telling a bunch of people why he remembers and fights for the mediocre. The "Old Man" (I could see Darren McGavin in the role: shades of "A Christmas Story") is no one special: he's just an old man who has a gift for remembering the past. As even he admits, neither he nor what he remembers is anything special. But that's how you take down the rich, the powerful, the "experts".
In 'Leverage", the team take down the rich and powerful. But a) they're super-talented, and b) they're confrontational. The Old Man in "Abyss" is neither. He's just a nobody, but he can inspire because the past speaks through him. He doesn't confront the rich and powerful, or their representatives: he runs rather than fights. All he does is speak for the past. But oh does he speak.
The episode falls entirely on Gould's shoulders. Neil Munro is good, as he is in pretty much everything he is. I like his near-tearful telling the Old Man that he can't remember, and that's why he took the Old Man in. But that's pretty much small change. It all comes down to Gould, and his "Old Man". The episode couldn't function without him, and it's a credit to Gould that it does.
But to quote from "A Sound of Thunder", oh, how do I do go on. Watch the episode yourself if you can, and see what I mean,.
But that's just my opinion, I could be wrong. Watch it, and tell us what you think.