The Time War. The Doctor has been injured and brought to a Time Lord field hospital. His body glows with energy, but this is no regeneration into a future form - instead, the Doctor’s past faces begin to appear as he flits haphazardly between incarnations…

Staggering to his TARDIS, the Doctor sets out to solve the mystery of his ‘degeneration’. Who has done this to him? How? And why? From the Earth to the stars, across an array of familiar times and places, he follows clues to retrace his steps, encountering old friends and enemies along the way. Tumbling through his lives, the Doctor must stop his degeneration before he loses himself completely...

For the 60th anniversary of Doctor Who, Big Finish is producing Doctor Who: Once and Future, a celebratory series of monthly full-cast audio dramas, each focusing on one of the Doctors.

The special edition CD bundle, which includes numbered CDs, special bonus artworks and additional audio content, is available here:

◈ Doctor Who: Once and Future - Special Edition (CD) - NOW SOLD OUT!

The special edition download bundle, which includes extended audio extras and music suites, is still available here:

◈ Doctor Who: Once and Future - Special Edition (Download)

The eight stories are also available as separate single releases on CD and digital download. The standard edition does not include the extras contained in the special edition bundle. Standard bundles are available here:

◈ Doctor Who: Once and Future (CD)
◈ Doctor Who: Once and Future (Download)

Further information can be found here: Doctor Who: Once and Future - FAQs