The Bourne Supremacy

It's not necessary to see the first but certainly if you can rent the DVD it might make the second more enjoyable.

I'd recommend watching the first one first, even though the second won't be totally untintelligible without it. They're both very well-made movies.

Richard Chamberlain starred in the mini-series of "The Bourne Identity" and more closely followed the book. The second film is garnering much better reviews than the first.