They joined forces with renowed producer and singer-songwriter Dallas Austin for their fifth studio album.
But despite working with a man who can count Michael Jackson, Madonna, Pink and Girls Aloud among his clients, McFly have admitted that they don't actually like the direction they went in for that LP.
And the boys said Above The Noise, which was released in 2010, is the worst one they've ever done.
Speaking to Digital Spy, Tom Fletcher said: "We thought we'd try something really drastic and try a completely different producer from a different genre of music."
Their record label Universal put them in touch with Austin and the lads said working with him was "a great experience and fun to shake it up a bit."
The album peaked at number 20 on the charts and 'Party Girl' was the first single released from it.
But they struggled to find a second single and Harry Judd explained: "None of us wanted to release 'Party Girl'. It was like a bad version of a Lady Gaga song."
And despite hating the LP, Fletcher admitted that the band have "fond memories" of it.
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