Amanda first appeared in the lead role of pathologist Sam Ryan in 1996, starring in 54 episodes before leaving in 2004, when her character returned home to Northern Ireland to be with her family.
Amanda Burton says: "I am so excited to be returning to Silent Witness and stepping back into Sam Ryan's shoes - with a difference! Audiences can look forward to plenty of twists and turns as they discover what Sam's been doing since leaving the Lyell."
Amanda joins fellow cast members Emilia Fox (Nikki Alexander), David Caves (Jack Hodgson) and Genesis Lynea (Simone Tyler) for six brand new episodes which will mark the 25th Anniversary of the hugely popular prime time BBC One drama.
Emilia Fox says: "It is such a delight and thrill to be working with Amanda. To have Sam Ryan back again at the heart of the show is the greatest way of all to celebrate the 25th anniversary of Silent Witness."
Lawrence Till, Executive Producer, BBC Studios Production, says: "I am delighted that Amanda agreed to return to Silent Witness for its Silver Anniversary. Silent Witness has a large and loyal audience and remains as popular as it has ever been with audiences regularly consolidating at over six million viewers. It is fantastic to have Sam Ryan at the centre of the series again alongside our other Lyell characters for a monumental story told in six parts."
Jo McClellan, Executive Producer for BBC One, says: "We are so excited for Amanda's return to the show in its 25th Anniversary year and the centenary of the BBC itself. It's a huge treat for audiences and a reminder of the legacy of this great drama over its many brilliant series and promises an exciting future for series to come."
Silent Witness 25th Anniversary series will broadcast next year, 2022.