NEW YORK — Look your last on "Rumpole of the Bailey," O woe, alas!

England's greatest second-rate barrister, Horace Rumpole (consummately played by Leo McKern), a stalwart of PBS' "Mystery" since 1981, appears in his last original one-hour courtroom mystery on Thursday.

Why? Why must it end? Such were the bootless cries in the midtown Manhattan hotel suite of former barrister John Mortimer, author and screenwriter of the Rumpole mysteries. Was it ... something we said? Had McKern tired of his character?

"I don't think it's anything to do with McKern," says Mortimer, who was in New York recently to promote "Murderers and Other Friends," the second volume of his memoirs. "I don't know whether he would like to do some more or not.

"It's partially the reorganization of British television, and it's partly that I just haven't written another television series," he says.. "I don't know that I never will."

It is Rumpole who contends not merely with the travails of criminal law, officious colleagues and bullying judges, but with the terrible will of his indomitable wife, Hilda--"She Who Must Be Obeyed."

Rumpole's passion for truth, justice, evidence and certain bloodstains has let him triumph, if only briefly, against all odds, while brushing the ashes of vile little cigars from his waistcoat and slurping inexpensive burgundy ("Chateau Thames Embankment") in Pommeroy's Wine Bar.

Mortimer, as if to appease the pain, says he is at work on yet another book of Rumpole stories.

"I've actually written a story which is told by Hilda, because I discovered there's a Jeeves story which is actually told by Jeeves--not a good one, but at least it's peculiar," Mortimer says.

They join the nine Rumpole volumes in the Mortimer oeuvre, alongside many plays, novels and classic screenplays--"Brideshead Revisited," "A Voyage Round My Father," "Paradise Postponed" and "Titmuss Regained," among them.

Mortimer said he is hanging up "Rumpole" because the private companies controlling Britain's commercial TV have become ratings-driven, "very much more like American television, which is sad.

"For some dotty reason, the whole of the commercial output is controlled by one man, a scheduler, who is appointed by all the companies. And he it is who tells them what will go in the schedule and therefore what they can make.