Penelope Daught, bolje znana kot Polka-dot, je prisrčna in iznajdljiva 11-letna deklica, ki živi s svojo bolno materjo Frances.Da bi zaslužila nekaj denarja in tako pomagala svoji bolni materi, Polka-dot očara krajevnega policista Cooperja in ga prepriča, da ji za skromno plačilo dovoli čistiti hišico njegovega službenega psa Lueyja. Deklica in štirinožni policistov spremljevalec kmalu postaneta prijatelja. Stanje bolne Frances se še poslabša in Cooper je soočen s kruto resničnostjo položaja mlade Penelope. Potrebno bo obilo poguma, upanja in prijateljstva, da bo nenavadna trojica spoznala, da so ustvarjeni drug za drugega.
COOPER BRAWN (40s) is a cynical, hard-nosed K-9 cop who spends his days tracking down bad guys and his nights hanging out with his surfer pals. And he wonders why his relationship with his ex-fiancé, SAMANTHA PHILLIPS (30s) didn't work out. Still, he hopes to re-kindle the romance. Samantha is upset at herself for still having feelings for Cooper and makes plans to move away so she can get over him. Then, spunky PENELOPE "POLKA-DOT" DAUGHT (11) enters Cooper's life by inventing a "Cops for Kids" program in which she helps take care of Luey at the Police Kennel. Charmed by the young ragamuffin, Cooper lets Polka-dot work, unaware she would eventually sneak into the kennel late in the evening to bring Luey home. Polka-dot lives with her mom, FRANCES (40s), who is battling a serious illness. To gain courage, Polka-dot identifies with her hero, Huckleberry Finn. After all, Huck was an orphan who navigated a mighty river on his way to a new life. Meanwhile, Frances' health declines to the point where she needs hospitalization. Afraid she will be sent to an orphanage, Polka-dot hides in a closet while the EMT's take Frances to the hospital. When Cooper finally learns the truth about Polka-dot, he confides in Samantha who is charmed by the deeply felt concern Cooper shows as he helps Polka-dot deal with the loss of her mom. What had been a lost relationship between Cooper and Samantha now comes back together as their engagement is re-kindled... and they officially welcome the charming and wonderful Polka-dot into their lives as adoptive parents.