Can't Do Everything

Alex Lachapelle thought that life really couldn't get any better. He and Helen just gotten married; secretly of course, because her family seriously disapproved and his buddy Richard wouldn't have approved either, given that he'd had an eye on Helen as well. But Richard had never had a chance from the moment Alex and Helen had laid eyes on each other.
Alex's first novel-a thriller, drawing on his experience as a former detective, about the connection between money laundering, murder and people trafficking in Chicago-had just been launched to rave reviews. Helen also had finally achieved critical acclaim as a photographer, with an exhibition of her work about to open at a major Chicago gallery.
Life was just about perfect.
Then Alex received an envelope, containing instructions for killing someone in another part of the country.
The envelope also contained snaps of Helen with crosshairs composed onto the images. The message was clear enough...
DO THIS OR ELSE
FOLLOW INSTRUCTIONS TO THE LETTER
NO TALKING TO ANYONE
OR SHE DIES