The Magic "cast" Roundabout. 

The practice of TV programme producers using one of the same small group of supporting cast actors in different programmes, because they choose "characters" rather than actors, thus there's no time wasted "getting themselves into the part" required.

These actors will play similar characters to that which they played in another recent drama, some as in period dramas, even wearing similar costumes to those they wore before.
It seems that sometimes, as soon as these people "exit stage right" in one drama, round they come again "entering stage left" in something else.

"The Magic Roundabout" is the title of a children's stop-action cartoon series. A roundabout being shown during the opening credits

In the BBC medical series "Bodies" Chrissy Farrell was seen each week as the hospital's departmental manager Vicky Hall.
A week or so after this series ended, she turned up in another BBC medical soap, "Casualty," as a patient in a ward bed, but she played her part no differently, same north-eastern accent. It was as if "Vicky Hall" had had an accident and was suffering from amnesia.
She'd been on The Magic "cast" Roundabout. "Magically," appearing as someone else almost immediately after she'd disappeared from another drama.

It happens in films, but not so frequently, an example would be Elisha Cook Jr. who played a petty small time crook in dozens of films.

The Magic "cast" Roundabout. by Doghouse Riley October 14, 2007