Mark is absolutely right about this being a custom monogram. The interwoven characters is the proof it's not a font.

If you have graphics software, like Illustrator or Freehand, you can do this sort of thing using any suitable font. (Bitstream Arrus has a somewhat similar serif style, but would need lengthening/narrowing if the letters were to approach this look. There are probably better candidates, if you don't worry about the serifs.)

For Monogram fonts, you might consider the selection of Harold Lohner in his Monogram Collection, especially the Script versions.