The New Teacher

This is a pretty funny sketch I came across from the British version of Comic Relief in 2007. It features Catherine Tate, who's best known to American audiences for the U.S. version of The Office, playing regional manager Nellie Bertram for the show's final two years. And also making an unannounced surprise appearance is David Tennant, who at the time was starring in Dr. Who for several seasons. Interestingly, the year after this sketch, Tate herself joined Dr. Who for a season.

I will admit to not catching all the jokes, but the live audience there seems to love them. And overall, it's a wonderful done piece where, as good as Tennant is, Tate just chews up the scenery.

https://www.youtube.com/watch?v=WxB1gB6K-2A