S5 E1 • The Dirtiest Business Part 1: A Spy is Born

After an attack on the lab by the SIS, Mike tries to help a girl who may become a Tomorrow Person escape from the KGB.

Première diffusion : 28 février 1977

S5 E2 • The Dirtiest Business Part 2: A Spy Dies...

John, Liz and Mike try to save the Russian girl from both the British SIS and the Russian KGB, with mixed success.

Première diffusion : 7 mars 1977

S5 E3 • A Much Needed Holiday, Part 1: Spilled Porridge

After the Death of Pavla, the Tomorrow People decide to go on Holiday, so Timus sends them to do an archeological dig on the planet Galia. There they run across two excaped slave boys.

Première diffusion : 14 mars 1977

S5 E4 • A Much Needed Holiday, Part 2: Just Desserts

With Mike a slave inside the alien's camp, the other Tomorrow People attempt to drive the alien slavers off Galia.

Première diffusion : 21 mars 1977

S5 E5 • The Heart of Sogguth, Part 1: Beat the Drum

After Mike's band, �The Fresh Hearts� plays at a gig, a man named Jake asks Elizabeth if he could become the band's manager. This offer excites the band, but Elizabeth thinks that Jake is a cheat and a fraud. At a rehearsal Jake asks Mike to play his drums to the special rhythm on a metronome, but the cleaner working in the room starts to act very strangely, and has to be taken outside to recover. Jake says it is their music that affected her, and arranges for music television producer Mike Harding to watch the band play that evening. Harding is impressed, and arranges for them to play live on television. Elizabeth discovers that Jake is actually Professor James Marsden, leader of a religious sect known as the Hearts of Sogguth. She persuades John of infiltrate the group, and he is initiated into them, but thinks they are harmless. Jake gives Mike the Heart of Sogguth drum to play, but warns him not to play the special rhythm. Elizabeth takes John to watch the Mike's band play at the disco, and they are introduced as the Hearts of Sogguth by Jake. Mike plays the drum to the special rhythm affecting everyone in the room except for Elizabeth. She jaunts onto the stage and stops Mike, but then finds that John is acting very strangely. Elizabeth jaunts back to the Lab, telling Tim that she thinks that John and Mike are under someone's control.

Première diffusion : 28 mars 1977

S5 E6 • The Heart of Sogguth, Part 2: Devil in Disguise

Jake tells John to stop Elizabeth telling anyone what happened, and gives him a knife. John jaunts back to the Lab and tries to kill Elizabeth, but his instinct not to kill breaks Jake's control. Mike and Jake go to the Hearts of Sogguth headquarters, but during a strange ceremony a voice warns Jake that Mike is different. Elizabeth finds an old book that predicts that Lord Sogguth will return when a million people hear the beat of his heart, and that he would destroy the Lords of the Heavens. Elizabeth thinks that the television broadcast will reach more than a million and the Lords of Heaven could be the Galactic Trig. The Hearts of Sogguth capture Mike, and something comes out of the sacred drum and takes control of him. When contacted telepathically by John and Elizabeth, Mike lies, saying that he is at home, and that the television programmed is the next day. John and Elizabeth jaunt to the Hearts of Sogguth headquarters to try to destroy the drum, but are discovered by Jake, who makes John attack Elizabeth. Jake tries to stab Elizabeth, but she jaunts back to the Lab. The next day Elizabeth jaunts to the television studio just before the broadcast; John tells Jake of her arrival, and persuaded Jake to let him stop her with a stun gun. Elizabeth is up on the gantry with a laser blaster, ready to destroy the drum, but is stopped by John before she can fire. Mike plays the drum in order to release Lord Sogguth, but Elizabeth manages to destroy the instrument. Sogguth is defeated, and, as he retreats back to the centre of the Earth, he takes Jake's soul with him, leaving behind just his skeleton.

Première diffusion : 4 avril 1977