Doctor Who: Out of Time 1

Out of Time was the first story in the Out of Time series, produced by Big Finish Productions. It was written by Matt Fitton and featured David Tennant as the Tenth Doctor, Tom Baker as the Fourth Doctor and Nicholas Briggs as the Daleks.
The Cathedral of Contemplation is an enigma, existing outside time. It turns through history, opening its doors across the universe to offer solace to those in need.
Occasionally, the Doctor drops in – when he's avoiding his destiny, it’s an ideal place to get some perspective. Only this time he's already there from several lives earlier, so when dimension barriers break down, his past and present collide.
And when the Daleks invade and commandeer the Cathedral, two Doctors must unite to stop them – or face extermination twice over!