Who are some primetime stars from successful series that couldn't follow through with their subsequent efforts?

Who managed several hits over the years?

Who kept plugging away and managed mini comebacks along the way?

Let's examine the trajectory of some of TV's most well known stars.

James Arness.

After a 20 year run on Gunsmoke, he came back a few seasons later with How the West was Won. It was a sort of mini series and did well. But in 1981 he was lured back to NBC for McClain's Law and it bombed against Dallas before being shuffled around to no ratings improvement. That was it for Jim.

Angie Dickinson

Policewoman was a 4 season hit but her alone series follow up Cassie& Co was a dud.

Who can you add to the list?

Mary Tyler Moore and Valerie Harper can be co-queens of this thread.