David Tennant stars in a triumphant 'Hamlet'

Even on a series as respected as PBS' "Great Performances" -- which is, after all, TV's longest-running performing arts anthology series -- some performances are greater than others.

So it's with great pleasure, and not a little relief, to report that viewers will get not one, but two (at a minimum) truly great performances in "Hamlet," airing Wednesday, April 28, on PBS (check local listings).

David Tennant, who recently left the role of the 10th Doctor on "Doctor Who," stars in the title role of this adaptation of the Royal Shakespeare Company's 2008 stage production in which he starred, opposite Patrick Stewart as his nemesis, King Claudius. It may seem like the kind of vanity casting that Broadway traffics in, with often ill-suited celebrities trucked in to pump up the box office, yet Tennant is really quite astonishing in the role, bringing the same quirkiness and wit on display in "Doctor Who" to the title role.

But make no mistake: This is "Hamlet," not "Whomlet."

Tennant, who performs much of this modern-dress performance in jeans and bare feet, plays his early scene as glumly as required for a young prince whose father has recently been murdered by his uncle, yet once his character hits on the notion of feigning madness, the Scottish actor starts spinning familiar words and lines like a virtuoso juggler with plates. The tragedy gets its full due, but this may be the least melancholy Dane ever.

"I had done some other work for them in the past," Tennant says of the Royal Shakespeare Company. "I had played Romeo for them. Possibly there was a sense of progression there, and I am not unaware that they thought the success of 'Doctor Who' would sell tickets, but whether they would not have offered me the part otherwise, you would have to ask them. I know that when you're successful in other media and go back to the theater, they always seem to welcome you.

"Obviously, it's both a huge privilege and a huge challenge to get to play that part for the Royal Shakespeare Company. But the RSC was definitely a familiar home of mine, and I had done work with them before. As had Patrick Stewart, who had worked there before he became a starship captain."

As for Stewart, he long had wanted to play Claudius yet simply never had been invited. And the chance to play the ghost of Hamlet's father as well was sheer catnip for the actor.

"For one thing, they're brothers, quite close in age, so if they look the same, it's actually very interesting," Stewart says. "Claudius is a great role because it is a depiction of a gifted, intelligent, bold man destined to be a great ruler who missed out and, as a result of missing out, chose a wicked option to achieve the life he wanted."

Stewart's formidable Claudius is only part of a riveting trio joined by Penny Downie, an Australia-born actress little known in the United States, who plays Queen Gertrude.