When Varun Made Samantha Cry

"Kasa kai Mumbai?!" Varun Dhawan's energetic greeting prompted hooting and cheering, as he waved to a packed auditorium at Mumbai's Mehboob Studio on Thursday afternoon.

It was a grand occasion to mark the launch of Citadel: Honey Bunny, which sees Varun paired opposite Samantha Ruth Prabhu in a dhamakedar spy action Web series combined with a tadka of their steamy romance.

The dynamic star duo set the stage on fire as they posed for shutterbugs.

They were joined by Director duo Raj Nidimoru and Krishna DK aka Raj & DK as well as their writer partner Sita R Menon and Prime Video India's head Nikhil Madhok.

Honey Bunny is the Indian chapter of Prime Video's global spy franchise Citadel that kicked off last year with Priyanka Chopra and Richard Madden. Anthony Russo and Joe Russo aka the Russo Brothers (Avengers) serve as co-producers.

WATCH: Raj & DK talk about their first meeting with the Russo Brothers:

The event saw the live performance by Shilpa Rao and Sachin-Jigar who crooned the romantic ballad from the series titled Yeh Safar.

Watch their live performance:

Later, singer Ash King performed the show's zippy title track that immediately pumped up the audience.

Watch the live performance here:

The most awaited moment arrived with the teaser reveal showcasing Honey Bunny's gritty and fast-paced action.

The exciting bit about the teaser is the action unfolding to the tunes of the '80s chartbuster, Raat Baaki, Baat Baaki from Namak Halaal, with Varun and Samantha navigating through the perilous mission in not seen before avatars.

Despite having no dialogues whatsoever, the chemistry between the two actors looks off the charts in their first outing as lead pair.

"It is a violent love story," Varun says with a smile as he recalls his first day where he was asked to punch Samantha.

"She was like, 'Hit me, hit me.' There's definitely a lot of hitting going on in this show for various reasons," he adds.

Samantha leaves behind the melancholy of her illness as she ups her action game after The Family Man 2.

But the path was perhaps not so easy.

Varun shares he saw Samantha succeeding through many challenges during the course of the show, which left him inspired by her "incredible work ethic".

"It's a public knowledge what she was battling when she joined the show. I thought my rehearsals were tough but then I saw her incredible work ethic despite her struggles, and it truly inspired me," Varun says.

"I've never been on a shoot or a creative process like that before, where I witnessed a co-actor going through such challenges. You learn a lot about human resilience and strength when you see someone battling something and still succeeding."

"Varun is being too kind. I am going to cry now," Samantha says emotionally, in this video.

When Samantha was asked how she deals with negativity amid her health situation, the actress admitted that it does get to her sometimes but she refuses to succumb to it.

"I do give up. I can't tell you I don't, but that's not where the story ends. I climb back up," she says.

Her candid response received loud cheers from her well-wishers.

Varun and Sam took the opportunity to treat their fans with a special surprise. They fired a smoke gun on stage that released Honey Bunny-themed tees with the actors' autographs inscribed on them.

WATCH: Varun tries to ape Samantha's "10-minute ice bath" to recover sooner from bruises. This is what happened next.

From doing "12 minute one-take action sequence" to shooting at "many real locations" without stunt doubles, Varun hails his streaming debut as a "great learning experience".

He reveals that Raj & DK warned him against taking up any other project to safeguard his look from the show, which he obliged.

"When you work with directors like Raj & DK, they are concerned whether you are starting another film or ad. When I took up the show, they had strictly told me, 'If you're doing this, you cannot do another film or shoot no ads because this is your look, you'll be only this'. I enjoyed it because I got to be in the character of Bunny for a longer period of time," Varun narrates.

WATCH: What left Varun angry on the sets of Honey Bunny? He shares the story in this video.

Staying true to his jovial nature, Varun called Raj & DK "kanjoos'" for not revealing more in Honey Bunny teaser.

The makers, in their defense, assured many surprises for the audience when the show drops on November 7 on Amazon Prime Video.