Two heavies turn up at Richard Diamond’s office and warn him that when he gets a call from a Mr. Barton he’s to turn down the job. However when Burton turns up he offers Diamond a $1000 to do the job and another $1000 on completion. Barton tells Diamond that his son, Roger Barton thinks he killed a man but Barton thinks his son has been framed and needs Richard Diamond to prove his innocence. 

After solving the case Dick sings It's A Big, Wide, Wonderful World. 

First show of the series.