saw girl from auntie episode on the internet last night(i'm assuming the title is a take-off on 'man from uncle'. I was wonder why emma peel isnt in much of the episode, was she trying to get out of the series or being difficult with her contract, and they were trying out a new sidekick??
shareThe production schedule for certain episodes allowed time off for the lead actors. It wasn't an issue with the actress being difficult. "The Girl From Auntie" shifts the spotlight to Patrick Macnee. Others episodes in the same season focused more on Diana Rigg like "The House That Jack Built" allowing her costar the chance to step back and play a more supporting role.
This way the show's leads were not exhausted from constantly being the focal point of every episode. When you only have two cast members, you need to be careful not to overwork them. Larger cast ensembles obviously don't have this kind of issue because the responsibility can be spread over more people.