Tonight on American Idol, the top 6 dove into mentor Andrew Lloyd Webber's songbook. Syesha Mercado started the night off with ''One Rock 'n' Roll Too Many,'' from Starlight Express. Webber predicted that Mercado would ''bring the house down,'' and the judges made him look prescient. Simon called her performance ''very sexy,'' and Randy told her ''it was your best performance to date.'' Next, an admittedly nervous Jason Castro sang ''Memory,'' from Cats, which Randy called ''a bit of a train wreck.'' Jason got no solace from Simon, who told him ''you were miserable throughout.'' Brooke White also disappointed the judges, burdened by a false start when she forgot the opening lyrics to ''You Must Love Me'' from Evita. Paula cautioned that in the middle of a live taping, ''you must never start and stop,'' but Simon brushed that off, and told her she made the right call to go for a do-over. Randy and Paula were much more impressed with David Archuleta, who put a pop-ballad spin on ''Think of Me,'' from Phantom of the Opera. Paula thought Archuleta was ''absolutely perfect,'' but Simon again had a contrary point of view, calling the performance ''weak'' and ''forgettable.'' In her segment with Webber, we learned that Carly Smithson had planned to sing a ballad at first, but she ran with the mentor's advice that ''Superstar,'' from Jesus Christ Superstar, was much better suited for her voice. Simon declared her performance one of his favorites of the night; she greeted this rare praise from Simon with a T-shirt bearing the slogan ''Simon Loves Me (This Week).'' David Cook closed the show with ''Music of the Night,'' from Phantom of the Opera. Randy and Paula thought he was ''amazing'' and ''fantastic.'' Simon, while not harsh on his performance, did make clear he preferred Cook's vocals ''gritty'' and ''raw.''

For a full analysis of tonight's show, check out Michael Slezak's TV Watch. And let us know who you think should go home by voting in our poll below.

Andrew Lloyd Webber Night: The Set List
Syesha Mercado: ''One Rock 'n' Roll Too Many,'' Starlight Express
Jason Castro: ''Memory,'' Cats
Brooke White: ''You Must Love Me,'' Evita
David Archuleta: ''Think of Me,'' Phantom of the Opera
Carly Smithson: ''Superstar,'' Jesus Christ Superstar
David Cook: ''Music of the Night,'' Phantom of the Opera

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