|Appearance||Black Feral Cat|
|Occupation|| Member of The Alley Cats|
Member of The Flushed Pets
|Residence||Streets of New York|
|Debut||The Secret Life of Pets|
|Voiced by||Bill Farmer|
Nitro is voiced by Bill Farmer.
Nitro is first seen eating fish bones in a trash bin, as Ozone tosses to him Duke's collar.
When The Flushed Pets is in the middle of the initiation of their new recruit, Max, Nitro screams "STOP!" and everyone looks at him. Nitro, with some other members of The Alley Cats, tells that Max and Duke aren't stray animals but pets, as they just robbed their collars earlier. Hearing this, Snowball orders the animals to catch the two dogs, but they can't get close to them because Duke bites Viper and swipes nearby animals, even Snowball is also thrown down to the water.
- Nitro is voiced by Bill Farmer, who is the voice actor of the famous Disney character Goofy. Bill Farmer also did the voice of Bob, a news reporter dachshund in Illumination's another film Sing.
|Buddy • Chloe • Duke • Gidget • Max • Mel • Norman • Pops • Sweet Pea • Tiberius|
|The Flushed Pets|
|Derick • Dragon • Nitro • Ozone • Password Snakes • Ricky † • Ripper • Snowball • Tattoo • The Alley Cats • The Sea-Monkeys • Viper †|
|Dummy • Gino • Guillermo's Iguana • Leonard • Marilyn's Cat • Myron • Peanut • Pepe • Reginald • Runty • Shelly • The Boston Terrier • The Collie • The Golden Retriever • The Papillon|
|Fernando • Maria • The Piranha • The Sausages (Frank • Timmy) • The Squirrels • The Pigeons • Unnamed Chihuahua|
|Animal Control (Fourrage • Menard) • Buddy's Owners • Chloe's Owner • Fred † • Harold • Gidget's Owners • Gino's Owners • Guillermo • Guillermo's Girlfriend • Katie • Katie's Grandma • Leonard's Owner • Marilyn • Mel's Owner • Molly • Norman's Owner • Pepe's Owner • Reginald's Owners • Steve Cabin • Sweet Pea's Owner • Tiberius' Owner|