In the bustling heart of New York City, we meet the charming magician, Hector P. Valenti, whose dream of stardom crumbles under repeated rejections from a national talent show. After yet another unsuccessful audition, he stumbles into an exotic pet store and discovers an extraordinary singing baby crocodile that he names Lyle. Believing this discovery could be his ticket to wealth and fame, Hector takes a bold step by putting his magnificent three-story Victorian brownstone house as collateral for their upcoming performance. However, during the crucial moment, Lyle suffers from an overwhelming case of stage fright, causing Hector to lose both the spotlight and the family home.
Fast forward eighteen months, and we are introduced to the new occupants of Hector's former domain—the Primms: Mr. Primm, Mrs. Primm, and their young son, Josh. Initially, Josh is plagued by anxiety over moving into a new place and struggles to make connections at school. But one fateful night, he stumbles upon the now fully-grown Lyle, who is residing in the attic. The two quickly bond as Lyle heroically saves Josh from a mugger, showcasing his unique singing talent in the process.
As both families start to intertwine, the Primms slowly warm up to Lyle despite their initial fright. They find common ground through shared hobbies and activities, forming an unexpected family unit. Just as things seem to be falling into place, Hector returns for a short visit, adhering to their mutual agreement that allows him to stay fifteen days a year. He once again tries to coax Lyle into performing, but the same stage fright prevents him from doing so—except for when he's entertaining his new friends, the Primms.
However, lurking below is the unfriendly neighbor, Mr. Grumps, who is anything but pleased with the disruption caused by this unconventional trio. Storming forward in his quest for peace, he sets up cameras to spy on the happenings upstairs, and eventually, resorts to bribing Hector to betray Lyle in exchange for cash to clear his debts. Caught in a bind and unable to express his good soul, Lyle finds himself trapped in a zoo.
Realizing the weight of his betrayal, Hector feels an intense wave of guilt and seeks to make amends by enlisting Josh's help to break Lyle out of captivity. Initially resistant due to Hector's actions, Josh comes around, and together they devise a plan. In a thrilling twist, Hector and Lyle manage to reconcile moments before the big talent show, where Lyle finally overcomes his crippling stage fright with Josh by his side, thrilling the audience with his vocal prowess.
In the aftermath, a trial unfolds to decide Lyle's fate. The judge delivers an unexpected ruling favoring Lyle when Hector reveals the deed to his house was actually under the rightful name of his grandmother, an animal-lover who founded the New York City Zoo and built the house. Following a triumphant verdict, the Primms celebrate Lyle's newfound freedom—and Mr. Grumps' implied eviction—by whisking him away on a cheerful vacation. Meanwhile, Hector's journey continues as he encounters a new, extraordinary animal talent—a beatboxing rattlesnake named Malfoy owned by Josh's friend, Trudy.
