Rihanna had an unidentifiable new man in tow when she showed up with an entourage to New York City hotspot, Avenue, on Monday night.

The pop star's latest flame "waited in her truck while she went inside," a source tells PEOPLE. "He waited for paparazzi to [go away], then he followed inside after her."

Included in her crew throughout the night was, Aziz Ansari, Busta Rhymes and Maxwell.

Clad in a white pin-up style dress, with black shades and Converse shoes, the "Where Have You Been?" songstress caught the eye of her controversial ex-boyfriend Chris Brown, who was also inside the venue with "a bunch of people."

"He looked over at her from his table across the way," a source tells PEOPLE. "His group was sipping Ace of Spades champagne and taking shots of Patron."

Brown, whose group was being "super nice," wore a white button-down shirt with a red jacket and glasses.
– Jennifer Garcia

She's got moves like … Hermione! Emma Watson got down at the Struck by Lightning Nintendo 3DS/Tribeca Film Festival after-party at Avenue in New York City. The actress had a dance-off with one of the film's stars, Roberto Aguire, as a DJ spun hits and partygoers looked on.

Also at the bash: the film's writer, Glee's Chris Colfer, supported by his FOX costars Amber Riley and Ashley Fink. The trio enjoyed appetizers and drinks and challenged each other to a spirited game of Mario Kart 7 on Nintendo 3DS. – Jessica Wedemeyer

No Growing Pains here – Alan Thicke was happy to party with son Robin and his wife, Paula Patton, at New York's Avenue. Joined by Queen Latifah and a few other friends and family members, the trio arrived shortly after the Mission: Impossible – Ghost Protocol premiere, and according to onlookers, seemed to be having a fabulous time. Though Robin donned a white T-shirt and jeans, the rest of the group was dressed to the nines, and spent the night dancing, chatting and sipping vodka drinks – though Alan and Patton stuck to Perrier and Diet Coke. – Jennifer Garcia

New dad David Beckham toasted the arrival of his baby girl, Harper Seven, with pals at Avenue in New York City Monday night. "They looked like they were having an amazing time," a clubgoer tells PEOPLE of the group. "He looked so happy – he was glowing."

Meanwhile, in the Big Apple, Vanessa Hudgens was dancing up a storm at Avenue with beau Josh Hutcherson. The two were "inseparable," a source says, adding that they "looked really happy together."

In the Big Apple, Fergie celebrated the two-year anniversary of nightclub Avenue along with her Black Eyed Peas bandmates. The group did a deejay set and took over two tables. Fergie also performed several songs and waved to Nicky Hilton before heading out with the socialite. Next stop? The ladies dropped by nearby Artichoke Basille's Pizza & Bar for some late-night grub.

Ashley Greene and rumored beau Jared Followill (of the Kings of Leon) were back at Avenue in N.Y.C. – and they looked very much like a couple. "Ashley was very flirty and affectionate with Jared throughout the night," says an onlooker.