Penny Peterson is the triagonist of the new 2014 animated movie "Mr. Peabody and Sherman." She is a classmate of Sherman who is also his rival, then love interest. She has blonde hair, a black headband and Mary Janes, white socks, a pink dress with white sleeves and blue eyes; she's voiced by Ariel Winter.
Penny is first seen being jealous of Sherman and gets into a fight with him because he knows history more than she. She rats Sherman on the principal, but Peabody insists that Penny and Sherman need to get along. Sherman tells her about the WABAC machine which gets Penny interested, and during their and Peabody's timetravel, possibly fall in love. More will be revealed as soon as the movie comes out.
In "MCF: Tricia and the Curse of Lake Blissful", she and Sherman witness Kari Kamiya being drowned by Violet Benton, the Siren which leads to Sherman calling the MCF, starting Tricia on her adventure.
She makes a cameo appearence in "MCF: The Revenge of Brad Starlight" where she and her friends are bored at her party, so Wander makes a pinata of Lord Hater for her and her friends to knock down. It is unknown how she knew about Hater, but it could be possible she witnessed from the earlier stories like "Shooting Stars" or heard about him through the MCF's adventures
- She is the second character that Ariel Winter voiced that has participated in the MCF series; the first was Sofia.
- Her relationship with Sherman resembles Alvin and Brittany of "Alvin and the Chipmunks" as well as Arnold and Helga from "Hey Arnold."
- It is also simular to Hiccup and Astrid of How to Train Your Dragon" and Jimmy and Cindy of Jimmy Neutron" because of simularity reasons.
- MCF: Tricia and the Curse of Lake Blissful(Debut)
- MCF: The Revenge of Brad Starlight(cameo)