Malcolm Webster was jailed for a minimum of 30 years for killing Claire Morris in a planned crash in Aberdeenshire in 1994 and attempting to kill Felicity Drumm in New Zealand in 1999 to claim insurance money.
The story has been made into an ITV drama called The Widower, with Reece Shearsmith playing Webster and Smith playing Ms Morris.
Her brother Peter Morris, who advised on the production of the three-part series, has praised the cast. He said: "Sheridan captured Claire completely. I miss that camaraderie of a sibling and I thank Sheridan for giving that back to me for a while.
"I feel as though if I want to see Claire again all I have to do is switch on this drama. At one stage off-set Sheridan hooked her arm through mine, and I told her it was exactly how Claire did it."
Former nurse Webster, from Guildford, Surrey, was given the life sentence after being convicted in May 2011 following a five-month trial, the longest murder trial against a single accused in Scottish legal history.
Sentencing him, Lord Bannatyne condemned his "cold-blooded, brutal and callous" crimes, which formed part of a fraudulent plot to pocket almost £1 million in insurance payouts.
Webster claimed the death of Ms Morris was a tragic accident that happened when he swerved to avoid a motorcyclist. The jury heard the killer drugged her before driving the car they were in off an Aberdeenshire road and starting a fire while she lay unconscious inside.
In 1999 he tried to murder Ms Drumm in a copycat car crash in New Zealand in an attempt to claim more than £750,000 of insurance money.
Police started probing Webster's past when one of Ms Drumm's sisters contacted British police in June 2006 to report her suspicions about him. Forensic tests on a tissue sample from Ms Morris's liver revealed she had been given a sedative before the crash.