I’ve been posting a good bit on acting on tv, with excursions into the movies and the stage, noting (frequently) that a great many of these people have extensive careers, with large numbers of acting credits, especially on television — where series (of several types) have an almost inexhaustible appetite for competent actors. So some people will pop up again and again. Some have a degree of celebrity, others are familiar faces you might not be able to put a name to, and even the well-known will often be cast in parts that have little to do with the characters they are famous for.
I’ve come to think of this bank of reliable actors as the Acting Corps. The American corps is largely distinct from the British corps — especially in sitcoms, where nearly disjoint sets of actors cycle through sitcom characters on the two sides of the ocean.
I’ll start with two reasonably well-known actors with extensive careers, one (John Ritter) already covered in some detail on this blog, the other (Tom Skerritt) mentioned several times here but not covered in much detail. Both have prodigious portfolios.