What Messiah ?
Handel wrote a piece of music called The Messiah.
But there is also a BBC TV series called Messiah
http://www.bbcshop.com/invt/bbcdvd1535
There may be other versions on Messiah as well.
A director is not the same as a conductor.
A conductor will rehearse an orchestra, and stand in front of them conducting the actual performance. A conductor usually conducts a group of musicians who are sitting down, although I guess they can conduct an Opera.
A Director (as in film, TV show, or Opera) will organise the actors or singers in the way they act, move around the stage, and if it is film or TV, where the cameras are going to be positioned for each scene.
So a conductor is mostly involved with musicians, a director with actors or singers.