This is an excellent adventure written by Robert Holmes, probably the best script writer the show ever had, and who wrote some of my favourite episodes including this, plus 'Spearhead From Space', 'The Ark In Space', 'The Talons Of Weng Chiang' and 'The Caves Of Androzani'.
The Galifrey set is looking a bit dated now, but it also looked quite low-tech in 1976 as well. What really makes this a special episode for me, is the brilliant plot, plus the Doctor going through the Matrix. The Matrix is an hallaguenic dream sequence with the Doctor facing imaginary threats from the Master, plus also being chased by a Bounty Hunter. The threat scenarios are very imaginative, for example: being shot at by a WW1 fighter plane, getting trapped on a railway line, having the water poisened, being almost drowned etc, and this together with 'Genesis Of The Daleks' are amongst the most violent episodes-ever, and by coincidence they are both directed by the brilliant David Maloney.
So to sum up, this is an action packed four-part adventure with great use of the BBC Quarry (again), plus surprisingly Kew Gardens for the tropical bits.
A superb Tom Baker era story from the long-running Dr Who series. This four part episode concerns the Doctors return to his home world Gallifrey, a plot to kill the president and the Doctor's pursuit of the assassin. Leading to the Time Lords ascention to the role of President himself before he slips off into space once more in his TARDIS.