Southern England, 1981. The universe has been saved, but at the cost of the fourth Doctor's life. The newly-regenerated fifth Doctor must rely on his friends to survive as the regeneration threatens to fail…

The TARDIS is plunging toward destruction. But even if the Doctor can escape, is yet another trap waiting?

The Doctor has arrived in the supposed safety of Castrovalva. But something is odd about the seemingly tranquil city…

The TARDIS crew are caught in a space-time trap. Escaping will mean a final confrontation with the Master.

Tegan steers the TARDIS to the planet Manussa, without meaning to - but why? And is it a coincidence that the planet is about to celebrate the 500th anniversary of the expulsion of the insidious Mara?

The Doctor talks to Ambril and Chela to try and stop the 500th anniversary celebrations. A possessed Tegan finds herself in Dugdale's Hall of Mirrors to where she summons Lon. The Doctor and Nyssa return to the caves.

The Doctor and the original snakedancer Dojjen work to rid the planet of the Mara.

After receiving a warning from the White Guardian, the Doctor initially believes the TARDIS has landed aboard an Edwardian clipper ship - but all is not as it seems. While the time travellers are caught up in the omnipotent Eternals' race for the ultimate prize, the Black Guardian's scheme to destroy the Doctor enters the end-game - but which side is Turlough a pawn of?

Captain Striker and his officers reveal themselves to be Eternals, mind-reading creatures who live outside of time and who require Ephemerals (humans and other "time dwellers") to relieve them of their emptiness. They race against other Eternals for the grand prize of Enlightenment, by which to grant their deepest wishes. That can't be good for the universe, but how can the Doctor strategise against beings adept at reading his every thought?

Turlough's panic puts him aboard a pirate ship where Captain Wrack uses his presence to invite all the other captains over for dinner. She's been picking off a few of her greatest rivals in the race and now sees an opportunity to clear the field once and for all and become the clear winner.

Tegan isn't aware she been outfitted with a device to destroy Captain Striker's ship. While the detonation will merely slip the indestructible Eternals back into the realm of eternity, nothing nearly so elegant or as tidy awaits the Ephemerals aboard the ship.

Lanzarote, 1985. Archaeologist Howard Foster raises a strange metal artefact from the sea floor. But how is it linked to the signal the TARDIS received? Why is Turlough suddenly so worried? And why is Kamelion acting so erratically?

While the Master, victim of his own attempt to improve his TCE weapon, seeks restoration through Sarn's numismaton gas, the truth of Turlough's past comes out at last, though to guarantee the safety of his brother and the Sarn people, Turlough must consider a great personal sacrifice.

Sarn prophesy foretells of an outsider who will come to aid the people. It's a role the Master is more than delighted to fill, which finally presents Timanov, the Sarn religious leader, the unbridled support he's sought in his campaign to cull the faithless from among his people. Turlough's secret past, however, is somehow intricately involved in all this, and the reluctance of its disclosure is enough to threaten all friendly ties with the Doctor.

While the Master, victim of his own attempt to improve his TCE weapon, seeks restoration through Sarn's numismaton gas, the truth of Turlough's past comes out at last, though to guarantee the safety of his brother and the Sarn people, Turlough must consider a great personal sacrifice.

Created for the 2009 DVD release of the Black Guardian Trilogy, this new 75-minute edit of Enlightenment was supervised by original director Fiona Cumming, and features all new CGI effects and a Dolby 5.1 Surround Sound mix.