Activity for Carly

My dress is a sheath silhouette with a V neck as well as V back and I need some sort of undergarment, supportive (no straps because dress straps are transparent) and preferably shaping. Any experience or suggestions?

My dress has a mild V-back and a plunging neckline with lace straps so I'll need a strapless, low-back bra/bodysuit for under my dress. Neither are super deep, but looking for something supportive. Any recommendations?