Sean Astin, who starred as hobbit Sam in The Lord of the Rings films, is joining the cast of hit TV series 24.
Sean Astin's character in 24 has not yet been revealed
Fox said season five of the real-time drama would continue where the previous series ended.
It is not yet known who Astin, 34, will be playing. The show is currently nominated for 11 Emmys, including best drama and best actor for Sutherland.
Spy thriller 24 is set in real time, with each episode covering one hour in the life of the programme's characters.
Kiefer Sutherland has won critical acclaim for his role in 24
The series will be screened in the US in January and a spin-off series of one-minute dramas designed to be viewed on UK mobile phones is also being made.
Fox will introduce the service to high speed mobile phone users in 23 other countries later next year.
Its first series in 2001 saw central character Jack Bauer, played by Kiefer Sutherland, attempt to thwart an assassination attempt on a presidential candidate.
He also had to rescue his family during the critical 24 hours.
The third series of the drama stalled in the US television ratings, losing two million viewers compared with its second series debut.
Astin starred in all three Lord of the Rings films, with the last one making a clean sweep at 2004's Oscars, winning 11 in total.