Star Trek: Lower Decks somehow manages to make Star Trek: The Original Series' "The Trouble With Tribbles" even weirder. Over the past one-and-a-bit seasons, Star Trek: Lower Decks has had more Easter eggs than Jean-Luc Picard has Earl Grey teas, and season 2's "An Embarrassment of Dooplers" alone includes a Guardian of Forever statue, an old Riker rival, Data/Lore bubble bath, and a stall selling krada legs. Not to mention literally everything seems to have been manufactured by "Quark's." However, the episode's plot is something of an Easter egg itself, closely mirroring a classic adventure from Star Trek: The Original Series.
"An Embarrassment of Dooplers" begins with the Cerritos escorting a Doopler diplomat. These well-meaning pink aliens duplicate whenever they feel anxious, emotional or embarrassed, and despite the best efforts of Captain Freeman's crew, it's not long before one offended Doopler turns into thousands, covering every deck of the ship with their paranoia. Freeman eventually discovers that Dooplers can be re-merged by angering them, and the Cerritos insults itself to safety. After being denied admittance to Starfleet's fancy annual party, Freeman has the Doopler transported into the ballroom as revenge, embarrassing the creature into mass duplication and ruining the whole event.
This storyline is a close echo of Star Trek: The Original Series season 2's "The Trouble With Tribbles." Similar to its Star Trek: Lower Decks counterpart, "The Trouble With Tribbles" begins with the main crew granted shore leave on a starbase. Uhura buys a pet tribble to take back to the Enterprise, but underestimates the creature's ability to reproduce. Kirk's ship is very quickly crawling with dangerous amounts of miniature fluffballs, but the situation is solved when Scotty beams every tribble on the ship onto a rival Klingon vessel, making the warriors even more angry than they were already.
There's a lot of crossover between "The Trouble With Tribbles" and "An Embarrassment of Dooplers," even down to the title itself. Both stories revolve around a starbase excursion (Deep Space K7 in TOS, Starbase 25 in Lower Decks), and both the Cerritos and Enterprise get swamped by relatively harmless creatures suffering a multiplication problem. Finally, each episode concludes with the offending duplications transported into "enemy" territory - a Klingon vessel for TOS, and a party full of Starfleet snobs in Lower Decks. Typically, Star Trek: Lower Decks makes things much weirder by introducing the Dooplers as sentient beings. The tribbles were essentially space rabbits who couldn't keep their libidos in check, but the Dooplers are fully aware of their duplication problem, and the more aware they become, the more they duplicate. It's basically what would've happened to the Enterprise if tribbles could talk.
Despite riffing heavily on a classic, "An Embarrassment of Dooplers" works perfectly as a spiritual successor to "The Trouble With Tribbles." Released in 1967, the latter might've been one of Star Trek's cuter moments, but also highlighted the political maneuvering of Gene Roddenberry's futuristic world, with Federation and Klingon ships clashing in a tale of sabotage and diplomacy. Star Trek: Lower Decks covers the same themes with its Doopler story, as the crew desperately try to avoid offending their guest, and Starfleet's elite refuse entry to the "lowly" Cerritos crew. Star Trek: Lower Decks might take the original concept to new heights of ridiculousness, but that's exactly what fans have come to expect.