This show has driven my husband and I crazy for over a year now, as we just cannot recall what it was! It is a comedy, the particular scene we recall takes place over dinner in a somewhat formal setting with attendees around a large table and one Englishman saying to another (across the table) repeatedly, "I know you" in a rather upper class, almost adenoidal, English accent.
I know this isn't much to go on, but it is all that I recall and I'd love to know what it is so I can see it again!
Can anyone help?

My guess is it might be "You Rang M'Lord". It could have been Michael Knowles saying it, but as you say it could have happened in about half a dozen programs, unless someone remembers it exactly.
Any other Ideas anyone?

I agree it might be "You Rang M'Lord", I can almost hear it being said now that you mention it.

Do the names Miss Poppy and Miss Lavender ring any bells? Was there a rather butch young lady and a fat crafty butler? Could Su Pollard have been the maid?

Here are some of the cast, the servants

Sorry guys, not set during the War, more modern than that - my hubby's in Belfast at the moment, when he gets back I'll pick his brains (what's left of them after all the Guiness) for more detail but I recall it was a pretty ritzy looking dining room the characters where in and it is driving me absolutely nuts . . . I'm one of those people who usually remember everything (mind like a steel trap gone rusty me thinks) as this one has me stumped!