User:SOTO/Forum Archive/The Panopticon/@comment-45314928-20200525010944/@comment-1789834-20200525190837

River shared a bath with the Tenth Doctor in the novelisation of Day of the Doctor. She states that she's about to head to the Library and he knows what that entails. The Tenth Doctor is meeting River to gain knowledge of Zygons, thus being one part of a lengthy prequel to Day of the Doctor from the Tenth Doctor's perspective.