Penny Gadget is Inspector Gadget's niece. She is the deuteragonist of the series. In the animated series, she was voiced by Cree Summer in Season 1, who also voiced Susie Carmichael from Rugrats and All Grown Up!, Penelope from Barbie as Rapunzel, Kim from The Care Bears Movie, Miranda Killgallen from As Told by Ginger, and Elmyra Duff from Tiny Toon Adventures and Elmyra, Pinky, and the Brain and Holly Berger in Season 2 as Cree Summer was unavailable to reprise her role as her for Season 2. She was played by Michelle Tratchenberg in the first live-action film, and Caitlin Wachs (who also played Andrea Framm) in the second film.
However, she and Brain do most of the work because of Gadget's cluelessness and incompetence.
Penny secretly helps her uncle Gadget with his missions, but it is Gadget who ends up getting all the credit in the end, which actually is beneficial because if Claw knew Penny was the real hero, she'd be in serious danger.
Penny is Gadget's tomboy niece and she secretly solves his cases for him, which Gadget is totally unaware of. Penny loves her uncle very much and looks up to him. It is never explained if she and/or Gadget have any other family members in the TV series, movies, or spin-offs, but Gadget seems to be the only family she has got.
Penny foils Dr. Claw's plans, leaving Gadget to get all of the credit for doing so, even though he didn't do anything at all (or sometimes very little). This makes sense because Penny would be in serious danger, if she got the credit. Penny often snoops around M.A.D.'s hideout to find out what they are planning; however, she normally ends up getting caught by Claw's henchmen and she either escapes by herself or calls her loyal pet dog Brain to rescue her. But when she and Brain are both captured, Gadget becomes surprisingly useful and competent and goes out of his way to rescue his angel, Penny. Gadget loves Penny more than anything and spoils her rotten and he sees Penny as his baby girl. In the 2015 series, she is now a junior agent. She is a lot more flawed and active. She acts like a normal teenager when she's not on duty.
She is right-handed and very intelligent despite her cuteness and beauty and she is capable of hacking into almost any computer-based system. plus her watch is a great thing to save her from danger.
Despite being fearless and a genius, Penny does have her flaws. It is shown in episodes such as Claw's Nephew, Gadget 2.0, and Eye of the Dragon that she has a strong weakness for boys and gets nervous when they're near her. She may be in love with Dr. Claw's nephews, William Thaw and Talon.
In Inspector Gadget's Biggest Caper Ever, she is noticeably more selfish, spoiled, and self-important. One of the many running gags was that she whines about a concert being sold out and ignores the fact that Gadget and the entire city was being terrorized by a dangerous pterodactyl. As karma, she is abducted by the pterodactyl and Gadget (out of extreme stupidity), ignores her pleas for help.
Penny has shoulder-length blonde hair worn in 2 pigtails. A possible episode of Gadget and the Gadgetinis may show some/all of her relatives with black hair. An episode of the original series may show some of her ancestors with blonde hair. In the 1999 live-action film, she has brown hair instead of blonde and wears her hair loose.
Her eyes vary between blue or green. In Gadget and the Gadgetinis and Last Case, her eyes are purple-blue.
Penny's age throughout the original animated series is 10 years old. 2 years later, she is 12 years old in Gadget and the Gadgetinis and Inspector Gadget's Last Case. 3 years later and she is 15 in the 2015 series. A year later she is 16 years old in the 2005 film Inspector Gadget's Biggest Caper Ever.
She wears a red short-sleeved T-shirt with a thick white stripe in the middle of her torso with olive green pants with knee patches, followed by red and pink sneakers. In Season 2, she wears a blue and white football jacket.
In the early 2000s, Penny wears a pink midriff shirt, a long sleeve turtleneck, brown baggy pants, and red sneakers. Her pigtails are also straight up. In Biggest Caper, she wore a red and white short sleeve shirt, blue jeans, and black sneakers.
In the 2015 series, she wears a red hoodie with white sleeve red boots, blue pants and red fingerless gloves, though occasionally she can be seen in her outfit of the original cartoon.
Penny is aged 10 throughout the original series, 12 in Gadget and the Gadgetinis and Inspector Gadget's Last Case, 16 in Inspector Gadget's Biggest Caper Ever, and 15 in the CGI reboot series.
Penny's last name is unknown. While Inspector Gadget's last name is Brown in the live-action film, the animated series strongly implies that Gadget is his real last name. While one can assume Penny's last name is Brown or Gadget, she frequently calls him "Uncle Gadget," suggesting that Gadget may be her maternal uncle or that he had his gadgets before Penny was born or before she met him.
It is never revealed why Penny is with Gadget and for some reason, the mere subject of Penny's parents are never brought up at all.
In the pilot, she is voiced by Mona Marshall, in the first season, she is voiced by Cree Summer, then in the second season, Holly Berger took over as the voice of Penny. In Inspector Gadget Saves Christmas, she was voiced by Erica Horn. In Gadget and the Gadgetinis, she was voiced by Tegan Moss (who also voices Holly Jollimore from Casper's Haunted Christmas) and in the 2015 cartoon, she is currently voiced by Tara Strong.