He appeared in school plays and on television before being cast as Alex Rider, the main character in the 2006 film version of Stormbreaker.
[4][6] Pettyfer was brought up in Esher and then Windsor, Berkshire and began his career initially being managed by his mother as a young fashion model at the age of seven, for Gap, after meeting Ralph Lauren in a toy store in New York.
[4] Before his GCSEs, he left Shiplake College to attend the independent Sylvia Young Theatre School in London.
[9] In June 2005, he was cast in his most prominent role so far, that of teenage MI6 spy Alex Rider in the film Stormbreaker, based on the novel by Anthony Horowitz.
One review of Pettyfer's performance described him as playing the role with an "earnest intensity",[10] although another noted that he "isn't quite at ease as an actor".
[12] At around age 17, due to his earlier acting success and to supplement his income, Pettyfer started modelling, notably in some advertising campaigns for Burberry.
[14] In 2009, he played the callous ringleader of a group of cool but cruel teenagers who are picked off one by one by the ghost of one of their former victims, in the horror-comedy Tormented.
[19] He was offered the part of Jace Wayland in the film adaptation of Cassandra Clare's best selling book, City of Bones.
[20][21] Pettyfer had also been offered a part in a film adaptation of Joseph Delaney's The Spook's Apprentice, but he declined the role.
[27] 2018 saw Pettyfer making his directorial debut in Back Roads where he also played the lead role of Harley Altmyer.
[28] In 2018, Pettyfer starred as Stephen Underwood, a journalist who uncovers the horrific murder of 22,000 Poles under Stalin's instructions, in the post–World War II thriller The Last Witness.
[29] In the same year, it was announced that Pettyfer had been cast in the main role of Brody on the Netflix science fiction miniseries The I-Land.
[31] In June 2009, Pettyfer was voted number 35 on British women's magazine Company's list of the top 50 most eligible bachelors.