You have to dig a bit to get back any kind of backstory for the Shalka Doctor.
DWM published a short story by Paul Cornell giving a brief history which rang fairly close to the history of the 8th Doctor in EDAs.
Of course he also left instructions to never refer to this had a series be commissioned.
I just checked back, the TVM is only 9 minutes long than Scream of the Shalka. Huh.
I was always upset there wasn't more Shalka, especially given how much I loved that version of the Master.
I actually wrote a short story about the Master for Kasterborous before they shut up shop.
I might have a copy sitting around if anyone wants a read...
