Plot

After three kidnappers lose the baby they have kidnapped, both the cops and kidnappers go looking for the baby.

Baby Bink couldn't ask for more: he has adoring (if somewhat sickly-sweet) parents, he lives in a huge mansion, and he's just about to appear in the social pages of the newspaper. Unfortunately, not everyone in the world is as nice as his parents, especially the three enterprising kidnappers who pretend to be photographers from the newspaper. They successfully kidnap him then have a harder time holding onto him as he not only keeps one step ahead of them but also seems to be more than a little bit smarter than they are.—Murray Chapman <muzzle@cs.uq.oz.au>

Posing as experienced baby photographers, incompetent Mafioso Eddi, and his equally-maladroit henchmen, Norby and Veeko, manage to snatch adorable 9-month-old Baby Bink right under the noses of his mother Laraine and nanny Gilbertine. However, keeping the seemingly-helpless hostage imprisoned is easier said than done, as he proves to be more resourceful, and much more intelligent than his desperate captors. A frenzied hunt for him begins against the backdrop of Chicago's bustling and dangerous streets. How will his exciting day out in the city finish?—Nick Riganas

Bennington Austin "Bink" Cotwell IV (Adam and Jacob Worton), is a the nine-month-old mischievous baby who lives in a huge mansion in a suburb of Chicago with his parents Laraine (Lara Flynn Boyle) and Bennington Austin "Bing" Cotwell III (Matthew Glave), is just about to appear in the social pages of the newspaper.

Three klutzy would-be kidnappers: Edgar "Eddie" Mauser (Joe Mantegna), Norbert "Norby" LeBlaw (Joe Pantoliano), and Victor "Veeko" Riley (Brian Haley) disguise themselves as the photographers from the paper and kidnap him, demanding a ransom of $5 million. After the kidnapping they have difficulty controlling him. While trying to get Bink to fall asleep, Norby does so reading Bink's book titled "Baby's Day Out", leaving him unattended. Looking through the book, Bink notices a bird on the page and then one by the open window. He follows it out and successfully gets away from his kidnappers, with Eddie falling off the building and into a garbage bin while chasing after him through the rooftop.

The FBI arrives at the mansion, headed by Dale Grissom (Fred Thompson), where they try to piece together clues along with Bink's parents and his loving nanny Gilbertine (Cynthia Nixon). Meanwhile, Bink now outside on the ground and crawling about, finds another part of his book: The blue bus, which he then boards. The kidnappers realize Bink is missing and start chasing the bus in their van but their efforts are in vain. Meanwhile on the bus Bink crawls into the bag of an obese lady who gets off at her stop shortly afterwards. By the time the trio catches it, and realize Bink is not on board, they then realize that he crawled into the lady's bag and follow her. An altercation ensues after they insult her, and while they attempt their escape, Bink crawls up to a revolving door at the entrance to a department store (also featured in his book) and is forced inwards by its momentum

Crawling through the department store, Bink is stopped by a worker (Dawn Maxey) who works for Mother Goose Corner, a nearby day care center, who believes he escaped from there. While unattended there, he crawls into the bottom of a stroller and is wheeled out by an unsuspecting mother, leaving the store, he crawls out from the stroller and eventually ends up in traffic after a ride on a taxi.

Meanwhile, Bink's parents receive a phone call from a concerned citizen Joe Depke who believes he saw Bink with a woman Mrs. McCray (Anna Thomson). Depke feigns memory loss when questioned until Mr. Cotwell pays him money. In the McCray's apartment the couple realize it's not Bink and apologize for the inconvenience. Mrs. McCray tells them she prays Bink will come back to them and knows how'd she'd feel if it were one of her kids. Just before leaving she tells Bing that she believes someone somewhere watches over the babies. The couple tell Mrs. McCray they hope she never is in their place for her children's sake & express hope that someone does watch over the babies.

The kidnappers attempt to follow him but get their feet run over by a passing truck and jump into a giant ditch as he makes his way to the city zoo. They find him in the primate house with a gorilla, and lose hope of gaining their ransom money. The gorilla shows a maternal side and does not injure him. The gorilla also feeds Bink with some of his fruits. The criminals attempt to retrieve him, but the gorilla thwarts them by pounding Veeko's hand, throwing Norby into the air using a mop as a catapult and finally grabbing Eddie close against the bars by roaring at him with intense volume and hurling him across to another cage.

The kidnappers eventually corner and catch Bink in the zoo's park, but are confronted by two friendly police officers, who have noticed that their van's engine is still running. During the conversation, Eddie hides Bink under his coat in his lap, but he reaches Eddie's cigarette lighter, sets his crotch on fire, and sneaks off as soon as the officers are gone. Veeko extinguishes the fire by repeatedly stomping on Eddie's groin, seriously hurting him.

They follow Bink to a construction yard, but are still unable to catch him, with Norby falling into a vat of wet cement, Veeko getting thrown off the building and into the back of a garbage truck, and Eddie getting stranded on a crane after being drenched in glue. The sun sets as Bink leaves the construction yard. The kidnappers manage to escape (offscreen) but decide to give up and go home.

Bink's parents are notified of various sightings of him in the city and Gilbertine deduces that he has been following Baby's Day Out and will most likely head for the Old Soldiers' Home next. Sure enough, Bink has made his way inside the home, where the elderly residents entertain him with a rendition of Irving Berlin's "This Is the Army, Mr. Jones." Laraine and Bing run in and joyously embrace Bink.

On the way home, he begins to call out for his "Boo-Boo" towards the criminals' flat. Laraine believes he is looking at the clock on top of the building and tries teaching him it's a "Tick Tock". Gilbertine again deduces he wants his book and tells Laraine there's no "Tick Tock" in the book. The recuperating criminals, upon hearing Bink calling out for his book, realize that he has returned, and upon looking out the window, to their shock, they find themselves surrounded by the FBI. They also find Bink and his parents standing outside the building as well. As Eddie berates Bink for ratting them out, Grissom forces the criminals to return Bink's book. As Eddie throws down the book, he, Norby and Veeko are arrested for kidnapping Bink and Bink is happy to have his book back and returns home with his parents.

Back at home, Bink is put to bed by his parents, who discuss having his photograph taken by a normal photographer in the morning while, unknown to them, he wakes up and gets ready to read another book titled Baby's Trip to China.