In a vibrant world where humans coexist with animated animals, we follow the antics of Tom Cat, a feline dreaming of becoming a pianist, as he relocates to Manhattan. He sets up camp in Central Park, meanwhile Jerry Mouse is on the hunt for a new residence. Their chaotic introduction begins when Tom's piano, which he plays while pretending to be blind to make money, is destroyed during a scuffle. This occurs when Jerry, trying to earn money by dancing in front of Tom's impromptu performances, gets caught, leading the crowd to retract their donations upon realizing Tom's deception.
During this commotion, Tom inadvertently collides with a young wedding planner named Kayla Forester, portrayed by Chloë Grace Moretz, resulting in her termination from the Royal Gate Hotel where she worked. Desperate to regain her footing and showcase her skills, Kayla cleverly fabricates a resume belonging to another job applicant and successfully lands a position at New York’s upscale venue, the Royal Gate, where she is tasked with organizing a high-profile wedding.
Within the hotel, Jerry's mischievous behavior continues as he pilfer food and various items to make his new home more comfortable, while Tom devises plans to infiltrate the hotel and capture Jerry. Opposing Kayla's hiring is Terrence, the hotel manager, who is skeptical of her capabilities. The Royal Gate Hotel boasts 260 luxurious rooms and 104 suites, with impeccable standards overseen by Chef Jackie Ken Jeong, a Michelin-starred culinary artist, and Joy the Bell Girl Patsy Ferran, a socially awkward bellhop.
As the video unfolds, we are introduced to local celebrities Preeta Mehta Pallavi Sharda and her fiancé Ben Colin Jost during their exciting arrival for the wedding. Unbeknownst to them, Jerry is already causing trouble by stealing from Preeta’s handbag. In a bid to alleviate the situation, Kayla suggests Ben take their pet Spike to a dog park for a discreet evening walk.
However, trouble ensues as Jerry's prankish antics are soon revealed, jeopardizing both the wedding and the hotel's tranquillity. Kayla offers to catch Jerry but quickly realizes that he is elusive and clever. After several failed attempts, Tom finally breaks into the hotel, leading to havoc when a fierce chase disrupts the ambience. Their noisy exploits trigger noise complaints, and during an encounter, Kayla finds herself teaming up with Tom, united in their mission to capture Jerry.
Kayla's recommendation leads hotel owner Mr. Dubros Rob Delaney to hire Tom as the designated exterminator for Jerry, with pressure mounting from Terence, played by Michael Peña, who warns them of dire consequences if they fail.
As the humorous struggle between Tom and Jerry ensues, including a failed attempt that sees Tom mistakenly attack Spike, the story takes several unforeseen turns. Jerry, taking center stage, cunningly reveals the location of Preeta's missing engagement ring as a bargaining chip to negotiate his stay in the hotel. Meanwhile, moments of chaos arise when misunderstandings lead to a grand destruction of the hotel's lobby, causing Kayla to not only retrieve the stolen ring but also alter the course of her career at the hotel.
Eventually, following the mayhem, Kayla rises to the position of event manager for returning the ring while Terence faces suspension due to his role in the incident. To maintain their places, Kayla instructs Tom and Jerry to put aside their rivalries and foster an uneasy alliance. However, their mischief leads to an unfortunate incident at a New York Yankees baseball game, resulting in their temporary imprisonment.
As tensions escalate and lies from a vengeful Terence set them against each other, the chaos climaxes at the wedding ceremony, where the duo’s antics culminate in a battleground of comedic disaster. Heartbreak ensues after Kayla's public humiliation forces her to leave. Yet, a change of heart from Tom and Jerry leads them to rally together, ensuring the wedding goes ahead, much to everyone’s surprise.
In a heartfelt resolution, they lure Preeta and Toots to Central Park for the ceremony, promising a peaceful resolution. Ben reconciles with Preeta, mending their relationship while Kayla finds common ground with the owner of the stolen resume. The film concludes with Tom pursuing his piano dream and a lively interaction with Jerry, leading to inevitable shenanigans once more.
In a whimsical post-credit scene, Ben finds himself confronted with a shocking bill for not one, but two weddings.
