Due to technical difficulties, you may never have heard about Lady Marjorie Bellamy's affair with her son James' friend, Charles Hammond.

Considering that Hammond died in an Indian cavalry attack, Lady Marjorie sank with the Titanic and James commited suicide before edoing a fund-raising tour of America this spring on behalf of public television, this gossip may e somewhat lukewarm. Even the television series on which these characters appear, "Upstairs, Downstairs," if defunct, the British producers having promised that they will produce no more genteel adventures among the teacups or saucepans.

However, there were 13 episodes shown in Great Britain which were not shown in America, either in the first run whic was completed last month, or in the re-runs now on Channel 22.

The reason is that because of a labor dispute, they were filmed in black and white only, and not for American color showings.

But while the technical crew was occupied with this problem, Lady Marjorie was busy elsewhere.

Annoyed at her husband for refusing to support the Conservative party in a division in Parliament, Lady Marjorie casts her eye on a cavalry captain who is waiting in the morning room for his friends James to change so they can go to the opera. One thing leads to another, and before you know it, the captain and the lady are off to see a gala performance of "Tristan and Isolde.

From there, it is but a step to the primrose path, and our dashing couple are soon spending their afternoons at his place in Chelsea, and not listening to opera, either.

The servants are all abuzz, having noticed that milady goes out a lot in the afternoons without the car. Even Bellamy gets the idea when Lady Marjorie, having heard that an officer was drowned in a regatta attended by Hammond, weeps with relief when Hammond walks safely - he thinks - through the door into the Bellamy drawing room.

Nevertherless, passion eventually subsides and we find Lady Marjorie at the opera again, where she tells Charles to get lost. In gratitude, her husband agrees to vote Conservative.

Now Bellamy has never told his wife that he noticed she was missing a lot that he noticed she was missing a lot at matinee time. So several episodes later, when Hammond has been killed in India, a clever blackmailer is able to collect from both Lady Marjorie and Bellamy separately when he presents her letters.

She buys back the letters so he won't know about them; he buys them to spare her the embarrassment of her knowing that he knows. And everybody lives happily ever after (especially the man has collected 200 pounds from each one of them), or at least for a few episodes.

And aren't you relieved to know that when the crunch came, Richard Bellamy acted like a gentleman and supported his party?