Ear, nose and throat specialists are sneezing themselves to death, each after receiving a mysterious empty envelope. When Tara is kidnapped, Steed takes great care over his morning mail.

Trusted agent Melville has lost three partners in quick succession, and seems to be lying at every opportunity. Is he really the man to partner Steed in an attempt to convict Lord Edgefield, noted blackmailer? And what is the odd connection between this whole affair and daily milk deliveries?

Anticipating the arrival of his enemies to kill him, millionaire Henley Farrer sets a deadly trap for them involving an Oriental dagger and, inevitably, Steed and Tara.

When agents find themselves in Colonel Mannering's interrogation centre, they think it's a test of their abilities, and relax with drinks when the sessions are over. But who's fooling who. Steed plays catch the pigeon.

Tara's uncle is being held against his will in a country hotel. So Tara books in, and finds herself equally discouraged from leaving. Could the place also be home to the agent that Mother is missing?

Security lapses seem to point to top civil servants suddenly falling in love and giving secrets to an enemy agent disguised as a char lady. Steed investigates, but first has to save Tara from killing herself out of unrequited love.

Steed, packing for a holiday, is knocked unconscious. When he wakes, he continues to pack but is confused when Tara arrives and tells him that he has been away for three weeks. Could it have anything to do with the mysterious man following him whom everybody else but Steed can see?

Whilst on a top secret security assignment, Tara comes under suspicion of being a double-agent. She must cast similar suspicion on Steed if she is to prove that she has been framed. An enemy agent, Gregor Zaroff, hopes to put the Government's new anti-missile defence system, code named 'Field Marshall', out of action by convincing Steed and Mother that Tara has betrayed the system's secrets. (Source: en.wikipedia.de)

It's Mother's birthday and he is visiting two of his aunts, Harriet and Georgina. To celebrate he tells them a hair-colour changing story, 'The Great Great British Crime'.

When Steed takes prime witness Miranda Loxton to a safe house to protect her from Murder-International hitmen, Tara is kidnapped. She escapes to find herself in her worst nightmare. A booby-trap in Steed's apartment kills Mother and Tara may be the only one with the hidden knowledge of where Steed has gone.

When a woman is found walking barefoot in a snowy field, complaining of a dead man who wasn't dead, Steed investigates the Happy Meadows funeral parlour, which doesn't seem to be keeping its clients down under. What connection could that business possibly have with Mystic Tours?