The 31-year-old presenter wasn’t afraid to bare all in a seriously sexy sheer number.
Donning an all-black ensemble, which featured a see-through design, the former Channel 5 star decided to forgo her underwear for the 71st BAFTA Awards.
Oozing sex appeal, the blonde bombshell wasn’t afraid to showcase her pert derrière as she strutted her stuff on the red carpet.
The London-based beauty flaunted her svelte physique in the tight-fitting garment as she smiled for the camera.
Revealing a tattoo beneath her bust, the star placed a hand on her hip for the pose.
Sian, who hosts her own evening radio show on Heart, let her golden tresses fall in loose curls around her shoulder.
The star accentuated her naturally pretty features with lashings of mascara and bold red lipstick.
Nominees and guests are expected to adopt the same all-black dress code as the Golden Globes 2018 last month, in solidarity of the Time’s Up movement.
“In 2018, we seem to have woken up in a world ripe for change. If we truly embrace this moment, a line in the sand will turn to stone.”
Stars expected to scoop a gong at the prestigious event tonight include I, Tonya actress Margot Robbie, Lady Bird star Saoirsa Ronan, and Daniel Day-Lewis for his performance in Daniel Day-Lewis Phantom Thread.
Hugh Grant, who is reportedly expecting his fifth child, is also up for the award for Supporting Actor for his role in Paddington 2.
The British Academy Film Awards ceremony will air tonight on BBC One at 9pm.