Perdita Rose Weeks (born 25 December 1985) is a British actress who currently plays Juliet Higgins in the CBS reboot series Magnum P.I. Weeks was born in South Glamorgan, to Robin and Susan (née Wade) Weeks, was educated at Roedean School in East Sussex, and studied art history at the Courtauld Institute in London. She is the younger sister of Honeysuckle Weeks and the older sister of Rollo Weeks, both actors. Portrayed Mary Boleyn in the Showtime historical drama The Tudors (2007–08). In 2008 she appeared as Lydia Bennet in the ITV series Lost in Austen. She played a murdering teen in the "Death and Dreams" episode of Midsomer Murders in 2003.
Weeks has worked on productions such as Stig of the Dump (2002), Sherlock Holmes and the Case of the Silk Stocking (2004), and Miss Potter (2006) and played the role of Kitten in the episode "Counter Culture Blues" of Lewis in 2009. In 2007 she appeared in the radio comedy Bleak Expectations, and in 2011 Weeks appeared in the TV miniseries The Promise.
Weeks co-starred with her sister Honeysuckle in Goggle Eyes (1993), and in Catherine Cookson's The Rag Nymph (1997): in the latter production she played the younger version of her sister's character. She also stars in the 2010 horror film Prowl, and the 2014 found footage horror film As Above, So Below.
In March 2018, Weeks was cast as Juliet Higgins in the CBS reboot of Magnum P.I., filming in Hawaii.