Third Doctor regenerates - Doctor Who: Planet of the Spiders - BBC
One of the famous regeneration scenes from renowned Sci-Fi drama "Doctor Who". Well, it needs no introduction. Here we see the changing of actors for the role of "The Doctor" to arguably the Proverbial measuring stick from what all past and future Doctor Who's are measured: Tom Baker. In online polls, Baker is nearly always voted as the best Doctor ever. Jon Pertwee, the third actor to play Doctor Who, regenerates into Tom Baker in this Youtube clip after being fatally affected by Metebelis crystals. What are they? Blue crystals from planet Metebelis III of course. Tom Baker only features for a microsecond in the clip. This regeneration is much different from the more modern day regenerations like David Tennant to Matt Smith, full of all the bells and whistles, cosmic rays flying all over the place. Pertwee just goes to sleep peacefully.
The Doctor's assistant who appears here is Sarah Jane Smith (played by Elisabeth Sladen), in which is the climax of the six-part "Planet of the Spiders". The strange broken-English character who appears is abbot K’Anpo Rinpoche, who is a Time Lord like Doctor Who, who has newly regenerated. A bit of a hippy, he leads a peaceful exile on Earth.
Jon Pertwee played the Doctor from 1970 to 1974. Tom Baker became the longest incarnation of the Doctor, and still, lasting 7 years from 1974-1981. David Tennant became the second longest running Doctor, with a good 5 years in the Tardis (2005-2010).