As the curtain fell on one of the most popular TV series in the world, the misanthropic but brilliant diagnostician Dr. Gregory House, played by Hugh Laurie, solved the most perplexing puzzle of them all - himself.

The series finale, called "Everybody Dies", began with a suicidal House trapped in a burning building, confronting his own demons and hallucinating.

Returning characters, including the dead Lawrence Kutner (Kal Penn) and "frenemy" Amber Volakis (Anne Dudek), ex- girlfriend Stacy Warner (Sela Ward) and Allison Cameron (Jennifer Morrison) appeared as figments of House's imagination in an episode packed with flashbacks.

Only Dr. Lisa Cuddy (Lisa Edelstein), who played House's on- and-off love interest, failed to make an appearance after leaving the TV drama a year ago.

The show's final weeks had left audiences wondering if the series would end with the death from cancer of House's only friend, oncologist Dr. James Wilson, or that of House himself - or both.

But in the bittersweet ending promised by creator David Shore, both men survived - at least for a while - with their long bromance stronger than ever.

As House finally opted for life and staggered to leave the fiery building, it exploded in flames. But as his colleagues gathered to praise and scold him in an emotional funeral, House had one last trick left up his sleeve.

He had faked his own death, destroying any chance of practicing as a doctor again, in order to avoid returning to prison after a disastrous prank and to instead spend time with the dying Wilson.

"I am dead Wilson," he quipped to his stunned friend. "How do you want to spend your last five months?"

The two men ride off on motorcycles into the sunset to the sound of the 1949 song "Enjoy Yourself (It's Later Than You Think)", as life goes on at fictional Princeton-Plainsboro hospital without them.

Monday's finale was preceded by a one-hour retrospective, celebrating the Emmy-award winning show's 177-episode history, its quirky characters and vast crew, video tributes by fans around the world and scenes from the final cast party.

Creator David Shore recalled how House and Wilson were inspired by the crime-solving British detective Sherlock Holmes and his trusty sidekick Dr. John Watson dreamed up by novelist Sir Arthur Conan Doyle more than 100 years ago.

And British actor Laurie said that playing House had been "an unforgettable part of my life."

According to the Guinness World Record, "House" is the most popular current TV show in the world with an estimated audience of 81 million people in 61 countries.

The series began in 2004, and Laurie won two Golden Globes and two Screen Actors Guild awards for his role. But audiences have slipped from a high of about 19 million in 2007 to about 8.5 million this year, and its producers and Fox television announced in February that the show would end in May.

(Reporting By Jill Serjeant)

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