The singer has rehearsed a "tongue-in-cheek" routine to his former boyband's song 'It's Gonna Be Me' along with his ushers and best man, The Sun reports.
"Justin has been working on this for months," an insider claimed. "Jessica used to love the track growing up and he wants it as a special treat.
"It will be very much tongue-in-cheek. There will be loads of exaggerated boyband moves and poses. She's going to love it."
The video for 'It's Gonna Be Me' memorably saw Timberlake and *NSYNC bandmates Lance Bass, JC Chasez, Joey Fatone and Chris Kirkpatrick made up as string puppets.
Timberlake and Biel are said to be tying the knot in a low-key ceremony in Italy.
The couple reportedly became engaged in late 2011 after an on-off relationship of five years, but Biel only confirmed reports this summer.
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