Geri Halliwell marked her 54th birthday with an unexpected guest: Hollywood legend Meryl Streep.

Halliwell, a member of the iconic Spice Girls group, shared photos on Instagram from her birthday celebration, which took place on the set of the Hulu series "Only Murders in the Building." In the images, Streep, 77, is seen planting a kiss on Halliwell's cheek. Halliwell described the encounter as "a moment she will always treasure."

"The best birthday present ever," Halliwell wrote on Instagram. "Spending my birthday with the extraordinary Meryl Streep was a moment I’ll always treasure. Thank you, @onlymurdershulu, for making it so special."

Halliwell has joined the cast of "Only Murders in the Building" for its upcoming sixth season. She will be appearing alongside Streep, as well as series regulars Steve Martin, Martin Short, and Selena Gomez.

Halliwell has prior acting experience, including a role in the 1997 musical comedy film "Spice World" and a recent appearance in the 2023 sports film "Gran Turismo."

The surprise pairing sparked excitement among fans, with many commenting on Halliwell's post with exclamations like "ICONIC" and "Omggg, Geri and Meryl Streep!? This is so cool!!!"

In separate news, Halliwell's fellow Spice Girl, Melanie Chisholm, known as Mel C, recently addressed a detail from her own wedding. Mel C, 52, married her partner Chris Dingwall last month in the Lake District. She confirmed that she had a lighthearted conversation with Halliwell about her choice to wear a white dress to the ceremony.

"I did have a little chat with Geri because it is her favourite colour," Mel C said on Australian radio. "She wears it every day. But she had a beautiful floral dress on and it was white white... I did have a little giggle with her about that."

Mel C also mentioned that Victoria Beckham was unable to attend the wedding due to prior commitments with her husband David Beckham and the FIFA World Cup final in New York. Despite her absence, Beckham designed Mel C's wedding gown.

Mel C's wedding featured several nods to the Spice Girls, including the group's music on the playlist and walking back down the aisle to "2 Become 1."