AceShowbiz - Kate Beckinsale knew how to honor Leonardo DiCaprio at his birthday party. The actress turned heads at the Hollywood actor's 49th birthday bash in Beverly Hills with her choice of outfit, which served as a perfect nod to one of Leo's biggest movies "Titanic".

The "Underworld" star joined other A-listers at the Saturday, November 11 soiree. For the party, Kate appeared to dress as the "Heart of the Ocean" necklace from "Titanic". She opted for a The Blonds minidress with a campy featuring a huge blue gem necklace that hung around her hip.

Her dress also had three rows of clear crystals adorning the bodice, imitating the necklace chain. "The Aviator" actress completed her look with platform pumps, a little black purse and a matching hair bow.

In addition to Kate, Kim Kardashian, Lady GaGa, Zoe Kravitz, Channing Tatum, Beyonce Knowles, Jay-Z, Taika Waititi, Tobey MaGuire and Snoop Dogg were among the famous names attending the party. Lil Wayne allegedly performed at the bash as "everyone was singing classic hip hop" at one point, according to an insider. The source also told PEOPLE that Leo was "raised and carried around the room."

It was also said that Leo and his girlfriend Vittoria Ceretti weren't shy in getting intimate in public at the bash. They were "affectionate and kissing throughout the night," the source claimed.

The lovebirds first sparked dating rumors when they were photographed getting hot and heavy in a club in Ibiza, Spain. The couple further fueled the romance rumors as he continued to bring the model to various events and parties around the world.

"They've been spending quite a bit of time together over the past few months, and they're enjoying getting to know one another on a deeper level," the informant spilled to Page Six back in September. The "Don't Look Up" actor appeared to confirm the rumors when he was seen out and about with Vittoria and her mom Irmelin Indenbirken at the Pinacoteca Ambrosiana Museum in Milan, Italy the next month.