Antonia Bernath

Bernath was born in London to English-Norwegian mother Sarah and American father Paul. Bernath spent her early childhood in Virginia. Driven by alcoholism, her father was physically and emotionally abusive. Bernath returned to England when she was 11 with her mother, who was diagnosed with cancer and unable to get treatment in the U.S. At 13, her mother passed away, and Bernath was subsequently brought up in Wiltshire by her maternal grandmother Audrey Goodrich.

Bernath attended Godolphin School in Salisbury and joined the National Youth Music Theatre. She began her studies English literature at Cambridge University, but changed her mind and decided to pursue acting. She graduated from Bristol Old Vic Theatre School on a scholarship. Bernath was the face of Johnson and Johnson Clean and Clear facewash for an International Campaign. She made her television debut in the 2003 Hogmanay special episode of Monarch of the Glen as Becky Body. She appeared in a 2004 installment of the anthology The Afternoon Play on BBC One.

In 2005, Bernath made her feature film debut in Kisna: The Warrior Poet as Katherine Beckett, making her one of the first leading British actresses in a Bollywood film. A Hindustan Times review declared her performance "good" and "cutely pleasing". That same year, she portrayed Priscilla Presley in the CBS miniseries Elvis (2005) alongside Jonathan Rhys Meyers, Randy Quaid and Robert Patrick. Her further television roles include portraying Lucy Bellham in Heartbeat, and Nikki Brown, a semi-regular, in Holby City.

Bernath went on to appear in the film St Trinian's in 2007, as posh totty Chloe, and can also be seen playing the Weather Girl for Radio Sunshine, in the Richard Curtis film The Boat That Rocked. She played a leading role, Charlotte Arc, in the 2009 ITV2 drama Trinity. alongside Charles Dance, Claire Skinner, and Reggie Yates. A review in The Morton Report described her performance in Trinity as "consistently strong".

Bernath was cast as jealous sister Jimi in British thriller film Cuckoo, co-starring Richard E. Grant and Laura Fraser. In 2012, Bernath appeared in Chariots of Fire on the West End, a stage adaptation of the film of the same title, as Florence Mackenzie, the fiancée of Eric Liddell (Jack Lowden). Bernath starred in the 2013 comedy films Stalled and Powder Room, the latter alongside Sheridan Smith. In 2015, she had recurring roles as Susan Borman, wife of astronaut Frank Borman, in the ABC period drama The Astronaut Wives Club and Laura Edmunds in the final season of Downton Abbey on ITV.

In video games, Bernath voiced Syanna in The Witcher 3: Wild Hunt – Blood and Wine, an Imperial Commander in Star Wars Battlefront, and as Dr. Emily Pope in Control. Bernath co-starred as Dr. Susan Gibbs in the Fox medical drama pilot Zoobiquity with Kim Raver and Peter Facinelli.

In 2018, Bernath joined 26 other celebrities at Metropolis Studios, to perform an original Christmas song called "Rock With Rudolph", written and produced by Grahame and Jack Corbyn. The song was recorded in aid of Great Ormond Street Hospital and was released digitally through independent record label Saga Entertainment on 30 November 2018 under the artist name The Celebs. The music video debuted exclusively with The Sun on 29 November 2018 and had its first TV showing on Good Morning Britain on 30 November 2018. The song peaked at number two on the iTunes pop chart.