I Love Trouble
(1994)

The mysterious "Ext 307" on the paper dropped from the pockets of the dead hitman in the elevator is the phone extension of senate staff member Sam Smotherman (Saul Rubinek), who really works for Chess Chemical and has organized the train derailment and the killings under the alias "Ernesto Vargas".

Reporters Peter Brackett (Nick Nolte) and Sabrina Peterson (Julia Roberts) are able to kill him and his henchman, and find the evidence that LDF causes cancer hidden in the ballpen that Peterson took from the dead luggage thief. Brackett and Peterson decide to keep their "accidental" marriage they had in Las Vegas, and go on a honeymoon.

 Thanks Tilman!