Musical surprises are tricky things. When you buy a ticket to a concert, wait in line for hours, and crowd in front of the stage like sardines, you have pretty high expectations for the performance you're about to see. Conversely, when you race past the shabby busker hauling out his rusty saxophone, you similarly have some idea of how it will go and often scurry to avoid hearing it.
But our expectations with music, like anything else, can be defied - sometimes to our delight and other times to our dismay. Unexpectedly horrendous performances can sometimes be even more entertaining than the ones that deliver the goods.
Here is a list of ten musical surprises - ten times musicians defied our expectations, for good or for ill.
This One's for the Underdogs
On August 11, 2009, a frumpy, middle-aged Scottish woman walked onstage at Britain's Got Talent in front of a crowd of thousands - with millions watching at home - and performed a selection from the musical Les Miserables. The results were unexpected, to say the least.
Okay, Cowboy, Tell Us How You Really Feel
It's not often one of the most famous country singers in America tries to cover a hit song from a leading industrial rock band.
Ukraine's Got Talent
I came across Vitas, a Ukrainian pop singer, while I was searching YouTube for performances of coloratura soprano voices. Imagine my surprise when some cute guy's face popped up in the search. Curious, I clicked.
The video opens with a catchy Euro-pop sound and bad choreography, but around 1:06 the song takes an unexpected turn.
Worth the Commute
What appears to be a crowd of everyday travelers at the train station bursts into song unexpectedly.
It Ain't Over Till the Blue Squid Sings
In this classic '90s sci-fi hit - a movie so wonderfully weird that it includes robot penguins and Ash from Alien playing a priest - a blue woman with a cephalopod for a head sings the famous mad scene from Lucia di Lammermoor. "Okay," you say to yourself, "it can't possibly get any weirder." And you're wrong.
Mariah Carey, Eat Your Heart Out
Mado Robin was a prominent coloratura soprano in the first half of the 20th Century. Singers like her are known for their high notes, but Robin was a cut above - literally. She had a knack for tastefully interpolating freakishly high notes into classical repertoire. Just wait for 2:40.
The Invisible Virtuoso
World-renowned violinist Joshua Bell is up for any challenge, including an unusual experiment to see how everyday commuters in the nation's capital would respond to top-tier classical music being performed at their metro stop.
The results were shocking. For the full report, read this incredible Washington Post essay. To watch, just click "play."
Some Things Money Can't Buy - Like Talent
Just imagine you're a ritzy New Yorker in the 1940s who's just purchased a ticket to a recital at the swanky Carnegie Hall. Ensconced in the plush red velvet seats of a place that hosts the greatest musicians of the day, you can't wait for the curtain to rise.
But when it does, the 76-year-old heiress Florence Foster Jenkins, a woman who spent years studying music but whose late husband had never let her perform in public during his lifetime, steps onstage wearing a pair of angel wings she made herself. Before you can decide if you're the victim of an elaborate joke or if there's merely been some mistake, she starts to sing.
One Last Hoyotoho for the Road
This one's for the opera buffs. Easily the greatest Wagnerian soprano of much of the 20th Century, Birgit Nilsson was known for a personality as big as her voice anda humility and humor that charmed sold-out audiences throughout her great career. In 1996 she spoke at an event honoring the conductor James Levine, and she gave him an unexpected salute at the very end.
Not Another Flashmob
Sadly, you can't think of musical surprises without thinking about flashmobs. These days, flashmobs are a dime a dozen, often part of some corporate media campaign, and are usually more meaningful to the participants than the viewers.
Fortunately some flashmobs break the mold, such as this breathtaking performance of Beethoven's "Ode to Joy" celebrating the 130th anniversary of a Spanish church. It brings tears to your eyes, in a good way.
When was the last time you underestimated a musician who ended up wowing you, or expected great things only to be dramatically - even comically - disappointed? Share your biggest musical surprises in the comments.