Twilight

A retired ex-cop and private detective (Newman) who lives with a rich actor (Hackman) who is dying from cancer and his actress wife (Sarandon) gets mixed up in murder when he is asked to deliver blackmail money. He walks into a 20 year old case involving the mysterious disappearance of the actress's former husband. James Garner appears as another ex-cop who also does occasional errands for the couple.