"A brief, if frenetic, introduction to Mr. Archibald Beechcroft, a child of the twentieth century, a product of the population explosion, and one of the inheritors of the legacy of progress. Mr. Beechcroft, again. This time, act two of his daily battle for survival. And in just a moment, our hero will begin his personal one-man rebellion against the mechanics of his age, and to do so he will enlist certain aids available only - in The Twilight Zone."
Mr. Archibald Beechcroft, who has had an insufferable time just trying to get to work, becomes annoyed when an errand boy named Henry spills coffee all over his suit. Taking some aspirin in the bathroom, he encounters a co-worker, Mr. Rogers, who advises him that he needs to keep fit to avoid headaches. Beechcroft explains that he doesn't drink, stay out late, or eat poorly. He's simply tired of being pushed around and wants to eliminate all the people of the world.
Later, in the cafeteria, Henry saves Beechcroft a seat, because he's still feeling guilty about spilling the coffee. He also presents Beechcroft a book titled "The Mind and the Matter", which deals with the ultimate in concentration. The book intrigues Beechcroft as he starts to reads through it in the cafeteria, and he continues to read it on the subway ride home. In his apartment, he reads the last page, and then concludes that the authors are indeed correct that concentration is the most underrated power in the universe. It then occurs to him that he can use concentration to realize his dream of eliminating people. He tests his theory out on his landlady, whom he successfully makes disappear. "Today, the landlady", Beechcroft smiles triumphantly, "tomorrow...the world!".
The next day, now that Beechcroft knows he can do it, he concentrates while in the subway and suddenly all the other commuters disappear. Beechcroft walks into usually overcrowded office to find it totally empty. Despite the paradise, he soon grows extremely bored; "bored to tears", with being the last person on Earth. After trying to create diversions such as an earthquake or electrical storm, Beechcroft goes home for the night, where he gets a visit from his conscience. Instead of learning from his mistake, Beechcroft comes away with the idea of repopulating the world in his image. This proves to be an even bigger mistake, since everybody else ends up being as anti-social, rude and cranky as Beechcroft. The people even look and sound like him.
His conscience convinces Beechcroft to return the world to the way it used to be, before his meddling. Things are definitely back to "normal" as Henry bumps into Beechcroft again, then asks him if he enjoyed reading "The Mind and the Matter". Beechcroft pretends to dismiss the book as "totally unbelievable", yet he knows he's learned his lesson.
"Mr. Archibald Beechcroft, a child of the twentieth century, who has found out through trial and error - and mostly error - that with all its faults, it may well be that this is the best of all possible worlds. People notwithstanding, it has much to offer. Tonight's case in point - in the Twilight Zone."