Jessica Biel see-through red dress black briefs A-team premiere London

Sheer madness: Jessica Biel flashes her unmentionables at the "A-team" premiere in London. Photo: Getty Images

Looks like Jessica Biel didn't bring her A-game to the London premiere of "The A-Team."

Oh, don't get us wrong. The beautiful starlet dazzled in a scarlet Giambattista Valli gown that matched the red carpet (perhaps a bit too closely) at the Leicester Square event.

There was just one teensy problem: The dress was see-through. (All those flashing bulbs didn't help Biel's flashing problem.)

Biel's high-waisted black briefs were visible underneath the semi-sheer frock, but whether it was intentional or not is anyone's guess.

On the bright side, at least the actress -- who rocked messy waves for the evening -- wasn't wearing a thong. Or the R-Pant.

Now that would have been embarrassing.

Meanwhile, see Kate Hudson's recent fashion faux pas.