Warning: this article contains SPOILERS for Abbott Elementary season 4, episode 10, “Testing.”Abbott Elementary season 4 included a massive guest star that highlighted one character’s significance at the school. Abbott Elementary season 4, episode 10 (“Testing”) follows Janine (Quinta Brunson) worrying over the results of a practice exam she gave her class, while Jacob (Chris Perfetti) encourages his quietest student to try out clubs. One of the episode’s subplots additionally brought in a new character to interact with Mr. Johnson (William Stanford Davis). Out of Abbott Elementary’s side characters and main cast alike, Mr. Johnson is one of the most memorable yet mysterious figures in the mockumentary.

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