A hugely enjoyable serial from start to finish. The Second and Third Doctor’s banter is hilarious to witness, and Stephen Thorne is excellent casting as Omega. This is one you can just watch over and over, and always find something new to appreciate.

This being the multi-Doctor adventure which started the tradition, it's hard not to see why multi-Doctor stories became as popular as they are today. Whilst it's a shame William Hartnell couldn't have a bigger role due to illness, Patrick Troughton and Jon Pertwee are hilarious together and form a entertaining double act.

The plot also adds some interesting details to Time Lord mythos; here, we meet the stellar engineer of time travel technology Omega (who was trapped in a anti-matter universe by the Time Lords). Omega is one of the best villains ever to be introduced in the show; he has a certain presence that makes you instantly fear him whenever he appears in shot. It's also a rare instance where the classic series look almost rivals the look of the monsters and villains in the new series; Omega's costume would not look out of place in the 2005 reboot of the show.

If you love Doctor Who and haven't seen The Three Doctors, then I urge you to watch it. For it showcases exactly what makes the traditional multi-Doctor adventure so great.