Melody Pond's second incarnation, going by Melody Zucker, or Mels for short, was Amy and Rory's childhood friend. Much like her friend, she believed Amelia's Raggedy Doctor to be real, rather than an imaginary friend.
Years later, when she at last met the Doctor, she held him at gunpoint to escape the police using the TARDIS, suggesting he took her to Berlin so that she could kill Hitler. When they arrived in Hitler's office, he tried to shoot the Teselecta, but ended up hitting Mels, who started to regenerate, finally revealing her true identity as their daughter.
Melody Pond regenerated into a toddler (TV: Let's Kill Hitler) in New York City in 1970 after developing a terminal illness. (TV: Day of the Moon) She spent years looking for Amelia Pond and Rory Williams, both of whom were born in 1989, (TV: The Eleventh Hour, COMIC: The Broken Man) and, under the name of Mels Zucker, (PROSE: Mels at School) grew up with them in Leadworth, (TV: Let's Kill Hitler) attending Leadworth Primary School with them. (COMIC: Imaginary Enemies)
Mels became Amelia's "second best friend", with the Eleventh Doctor coming ahead of her. Mels was the first person that she told about the Doctor, Rory only learning about him because Amelia had forgotten that he was hiding under the bed. (WC: The Raggedy Doctor by Amelia Pond) Mels dreamt about all the stories that Amelia told her about the Doctor and she decided that she would marry him. She was sent to the headteacher's office due to answering questions with reference to the Doctor and calling her history teacher stupid for not knowing about him. As a support figure, Amelia often waited for her outside of the headteacher's office and lectured her about her behaviour after these incidents. (TV: Let's Kill Hitler)
As the only person that Veronica Stackmore was scared of in Year Three, Mels scared her by dressing up in a mask and calling herself "the Sheep of Doom" when she stole Amelia's Raggedy Doctor doll. She proceeded to behead it before handing it back to Amelia, assuring her that it could be repaired with some tape and telling Amelia that the reason that adults did not believe the things that Veronica was doing was because adults were dumb and that she might "stay a kid forever". (COMIC: Imaginary Enemies)
When Krampus and his goblins invaded Leadworth, the goblins told Mels that they had heard "many stories" about her and tried to attack her, but she used her superhuman strength to stop them. Krampus later trapped Mels, Amelia and Rory by wrapping them in Christmas wrapping. When Veronica denied Krampus, he and his goblins vanished, leaving only Mels with memories of the incident. After the school nativity play in which her future parents played Mary and Joseph, Mels presented Amelia with her repaired Raggedy Doctor doll and agreed with Brian Williams that Amelia and Rory made a "lovely couple." (COMIC: Imaginary Enemies)
Holding the record for most confiscated property, Mels once had Amy and Rory cause a distraction so that she could sneak her confiscated items out of the teacher's supply cupboard. After doing so, she escaped over the roof and through the window of the teachers' toilets. (PROSE: Nothing O'Clock)
As a young adult, Mels drove a Mini Cooper and worked as a management consultant. (PROSE: River of Time) She remained irresponsible, however, once stealing a bus and driving it into a botanical garden, an incident after which Amy had to pick her up from the police station. She eventually helped Amy see that Rory was in love with her and that he was not gay as Amy believed him to be due to his lack of interaction with other girls. However, she did not attend their wedding, claiming that she "[didn't] do weddings".
In the autumn of 2011, Mels stole a car and, chased by police, followed her parents to a cornfield where she finally met the Doctor, holding him at gunpoint and demanding that he take her in his TARDIS to escape. When asked if she had anywhere specific in mind to visit, she jumped at the idea of time travel and decided to go and kill Adolf Hitler "for the hell of it". Inside the TARDIS, she decided to test the principle of temporal grace and shot the TARDIS, causing it to crash into Hitler's office in 1938 and save him from the Teselecta's assassination attempt.
When the Teselecta recovered, Hitler fired at it in fear, causing the bullets to ricochet. In the confusion, a bullet hit Mels in the gut. She got the Doctor to promise to marry her and revealed her true identity to the three of them. Beginning to regenerate, Melody reflected on her last regeneration and told her parents she was glad she had found them, before she exploded with regeneration energy and became her third self. At the time she was regenerating, she was focusing on a dress size. (TV: Let's Kill Hitler)
Mels was sassy, often in trouble and chased by police just before her regeneration. She resented the Doctor and blamed him for historical disasters, but wanted to marry him. She was quite reckless and daring, stealing vehicles to go on joyrides. Along with her rebellious behaviour, she had a dangerous curiosity that led her to fire off a gun in the Doctor's TARDIS to test out if it had a temporal grace blocking the use of firearms, which was a bluff. Her bullet pierced the time rotor and sent the TARDIS spinning out of control with a great volume of toxic gas pouring out of the hole it made in the damaged casing. Mels also liked to use the phrase "penny in the air...and the penny drops", when people around her were slow on the uptake to realise something that she clearly understood, then finally became aware of the truth. (TV: Let's Kill Hitler)