Halsey flashes her bra while Alessandra Ambrosio lets loose on the DJ decks at amfAR afterparty

The stars showed up for a good cause on Thursday when they attended the annual amfAR Gala in Cannes to raise money for AIDS and HIV research and awareness.

And after attending the posh soiree, the celebs seemed happy to let their hair down as they attended Johnny Depp and Richie Akiva’s after party.

Leading the stars was Halsey, who looked sensational in a sheer lace top that flashed her toned abs and black bra.

The singer, 28, paired the garment with a shimmering gold skirt, while sheer socks and heels enhanced her model-like physique.

It was a more vampire look than her prom outfit where she opted for a sleeveless flowing pink dress made of sheer material.

Another star who opted for a quick change was Alessandra Ambrosio, who modeled a silver sequin dress that showed off her toned figure.

At the party, she made sure all eyes would be on her as she walked over to the DJ deck and operated the microphone.

Earlier in the day, the model looked nothing short of incredible in a dangerously plunging silver dress as she attended the gala.

Alessandra shone in the bold silver dress with sassy beading that showed off her ample cleavage.

Despite being the host of the after party, Johnny Depp was nowhere to be seen at the bash.

The star-studded amfAR Gala Cannes took place at the legendary Hotel Du Cap Eden Roc Cap D’Antibes.

Queen Latifah hosted what is the most popular party at the annual Cannes Film Festival, which raises millions of dollars for AIDS and HIV research and awareness.

Guests enjoyed musical performances from Halsey, Adam Lambert, Bebe Rexha and Gladys Knight, while sipping Clase Azul Gold and Reposado tequila from Mexico’s first luxury spirit brand.

Clase Azul is Mexico’s first luxury spirits brand and makers of Clase Azul Reposado that celebrity guests sipped at the party.

The posh amfAR gala also included a fashion show, curated by Carine Roitfeld, and a fundraising auction by Simon de Pury.

Included in the auction were Cecily Brown’s latest work – created especially for amfAR – and a 2016 signed Damien Hirst artwork by Leonardo DiCaprio.

AmfAR Gala Cannes co-chairs include Angela Bassett, Kate Beckinsale, Robert De Niro, Ethan Hawke, Scarlett Johansson, Milla Jovovich, Eva Longoria and Heidi Klum.

amfAR, The Foundation for AIDS Research, is one of the world’s leading non-profit organizations dedicated to supporting AIDS research, HIV prevention, treatment education, and advocacy.

In April 1983, Dr. Mathilde Krim and Dr. Joseph Sonnabend, along with Michael Callen and several others in New York City, founded the AIDS Medical Foundation (AMF).

It was the world’s first private organization dedicated to raising funds to support scientific and medical research on AIDS. In 1984 the first research grants were awarded.

In September 1985, amfAR was formed through AMF’s association with the like-minded National AIDS Research Foundation, which had been established in August 1985 in California.

Since then, amfAR has invested nearly $617 million in its programs and awarded more than 3,500 grants to research teams around the world.

amfAR Gala Cannes has raised more than $245 million in total for amfAR’s life-saving AIDS research.