Doctor Who: Black Orchid

The Doctor has regenerated but it hasn't gone well. He's mentally unraveling and needs a place to rest beyond outside influences. Unfortunately the Master has laid a trap for the TARDIS that denies the Doctor undisturbed recovery time.

To avoid falling into Event One (the Big Bang), the Doctor must convert mass into momentum by having the TARDIS jettison a quarter of itself. Unfortunately it can not be known which rooms will be ejected.

The city of Castrovalva and its untroubled people would seen an ideal place for the Doctor to recover, but a dire warning from Adric, held captive by The Master, makes it seen less so.

The Portreeve of Castrovalva is revealed to be the Master in disguise who, as the Doctor discovers, created Castrovalva himself to trap his newly regenerated arch-enemy.

Instead of Heathrow Airport, the Tardis lands aboard a spaceship. The Doctor and his companions meet it's inhabitants, three Urbankans, and more surprisingly a group of humans of different nationalities and from different time periods.

Intrigued by the ancient humans on board the Urbankan ship, the Doctor and his companions decide to explore further. The Doctor and Tegan, separated from Adric and Nyssa, learn from Bigon the truth about the cultural representatives.

Monarch wins Adric over with his plan for humanity but Nyssa isn't so easily swayed. Meanwhile, Bigon reveals to The Doctor the nature of Monarch and the ship's android inhabitants while a panicked Tegan attempts to escape in the TARDIS.

The Doctor needs to stop Adric from siding with Monarch and get Bigon quietly restored (who was mechanically lobotomized for previously siding with the Doctor). The ship then gets turned into one big multi-cultural dance party so the Doctor can make a desperate leap for the TARDIS, floating just outside the spaceship, and stop Monarch's plans for Earth.

The Tardis lands on Deva Loka. While Nyssa recovers inside the Tardis, the Doctor and Adric meet a survey team and their hostages, the seemingly primitive and mute Kinda. Meanwhile Tegan is tormented by an evil entity in her dreams.

While Sanders leaves the dome and receives a strange box from two female Kinda, Hindle begins losing his mind and has the Doctor, Adric and Todd arrested. Meanwhile the Mara takes over Tegan's body.

Opening the box, the Doctor and Todd learn the truth of the Kinda and escape from Hindle to find the Kinda's wise woman Panna. Meanwhile the Mara, posing as one of their own, tries to bring the Kinda under it's control.

Led by the voice of the Mara inside Aris, the Kinda begin their attack on the dome. The Doctor, Todd, and an awakened Tegan attempt to stop the two sides destroying each other and hatch a plan to defeat the snake-like Mara.

Trying once more to return Tegan to Heathrow Airport, the Doctor instead lands the Tardis in the same location three hundred years earlier where he and his companions are chased by angry villagers but rescued by a charismatic highwayman.

To rescue Tegan and Adric, captured and interrogated by the Terileptil fugitive leader, the Doctor must get past the locals under alien control and overcome Death (an android servant dressed up as The Grim Reaper).

The Doctor makes the fugitive Terileptils a rare offer they shouldn't refuse; but, though few in numbers, they have a plan in the works for the quick and complete domination of Earth and mean to see it through.

With Tegan and Richard under alien control, and the manor sealed against anyone leaving or entering, it's a question whether or not the Doctor can get to London before the Terileptils release their improved strain of black death upon the world.

The TARDIS arrives in England, 1925, near to where a mysterious, gurgling man has escaped his bonds and started strangling servants. The Doctor is "expected" and taken (along with Tegan, Nyssa, and Adric) to the Cranleighs' country estate where The Doctor participates in a cricket match and Nyssa turns out to be the near spitting image of Ann, fiancée of Charles Cranleigh. They all stay for an afternoon costume ball. Tegan teaches others how to do the Charleston while Adric eats, but The Doctor finds himself searching through secret passageways in his bathrobe after the gurgling man steals his clothing and party costume to attend the ball and deal with one of the guests.

Ann escapes her Harlequin-clad abductor but it's The Doctor whom she accuses. Strangled bodies mount and The Doctor is arrested along with "accessories" Tegan, Nyssa and Adric. Will Lady Cranleigh's secret come out?

In the midst of an argument between Adric and the Doctor, the Tardis materializes underground in Earth's distant future where a team of paleontologists and geologists find themselves under attack from a pair of androids.

Disposing of the androids, the Doctor and Adric must deactivate a bomb that they unknowingly triggered. Setting off in the Tardis to find the culprits, they arrive aboard a freighter ship while the Cybermen watch their old enemy from afar.

Aboard the freighter, the Doctor and Adric are taken prisoner by Captain Briggs. The Doctor looks on in fear as his old foe, the Cybermen, begin to take over the ship in large numbers.

Tegan is captured by the Cybermen, allowing the Cyber Leader to use her as a hostage and force the Doctor to do his bidding. Left behind on the ship, Adric attempts to prevent it from plummeting to Earth as time is running out.

Following the death of Adric, the Doctor arranges a trip to Victorian London to lift everyone's spirits but the Tardis instead materializes at Heathrow Airport where a British Airways Concord has mysteriously vanished.

The Doctor's TARDIS is stolen, and tracking it down reveals the existence of an alien named Kalid controlling events in the past. While the Doctor challenges Kalid's motives for being there, Tegan and Nyssa discover the source of Kalid's power - an even greater threat for the Doctor.

The Master commandeers the Doctor's TARDIS, leaving the stranded Time Lord time to work out the mystery of the alien sanctum he's been trying to enter. Inside lies an immense power - the entire Xeraphin race, thought long lost but distilled into a single living essence, ready for rebirth but now suffering a dual gestalt personality, good versus bad, thanks to the Master's meddling with it. As the two Xeraphin halves enter into a struggle for dominance of the whole, the Doctor works for a favorable outcome before the Master can succeed at turning them into his new power source.

Incorporating the Xeraphin race into his TARDIS power system, the Master has won, but technical obstacles and a bit of sabotage from friendlies give the Doctor a bargaining chip for the lives of the hijacked and enslaved airline passengers and crews - with maybe, just maybe, some hope for the Xeraphin race as well.