And they left much to the imagination ahead of the drama’s release this November.
“The Doctor knows that River Song is a part of his future. A maddening, intriguing, but inevitable part,” their website reads.
“Their lives are becoming inextricably intertwined, but in these early days – for the Doctor at least – they must navigate their relationship without too many spoilers.
“Whatever her past, and the Doctor’s future, holds, River will make sure that he has fun untangling the mystery…”
The first instalment is called Expiry Dating by James Goss, and will see the Doctor with a big decision to make.