Murder by Natural Causes is a 1979 American television film directed by Robert Day and starring Hal Holbrook, Katharine Ross, Richard Anderson, and Barry Bostwick.
It is a crime mystery written by the creators of the TV series Columbo, Richard Levinson and William Link.
A successful mentalist, Arthur Sinclair (Hal Holbrook), preys upon wealthy socialites such as Helen Carrington (Eve McVeagh) for their money.
Weston is a would-be actor in love with Allison, and we soon learn she is planning to have Gil kill Arthur by scaring him to death (by overloading his weakened heart).
Their plan is to have Weston storm the house pretending to be a burglar – and then point his pistol at Arthur, who would supposedly die from the shock.