“They will always be defined by the roles they played. Robert Wagner is the suave star of It Takes a Thief and Hart to Hart. … Sally Field is The Flying Nun and Norma Rae. And Henry Winkler? He’s the Fonz. … They made their mark personifying youthful vigor in blockbuster hits; now they are starring in TV and YouTube infomercials promising to help seniors overcome the debilitating challenges of old age.”