The Mom star couldn't help joking about dating a "very cute" bodyguard while speaking with ET's Kevin Frazier and Nancy O'Dell on the red carpet.
"[This is] my Pamella Roland beautiful gown, and the first time I've had to have a guard because I have Chopard diamonds on," she dished. "They're actually heart-shaped rubies, if you look closely. It's the most beautiful necklace I've ever worn and I had to have a guard with me."
"He's very cute. I think he's single," she teased, before Frazier and O'Dell beckoned the "guard" over, only to realize he wasn't who Janney said he was.
"I'm only kidding. He's not my guard. He's my date for this evening. Now he's going to be mad at me," she said, laughing. "He's really cute. He's one of my best friends forever, who moved to London and now he's here at the Oscars with me and I'm excited."
Janney was full of jokes on the carpet, putting her own spin on ET's "Bought, Borrowed or Stolen" game. "Bought, borrowed or stolen? These jewels at the end of the night!" she cracked.
For the 59-year-old actress, the best part of the Academy Awards isn't the actual show -- it's the fashion. "I don't need to meet the people I idolize. I just need to see what they're wearing!" she confessed.
Janney -- who won Best Supporting Actress for her role in I, Tonya at the 2018 Oscars -- is, however, looking forward to seeing one star: Regina King. "I think it's her night," she said of King, who is up against Amy Adams, Emma Stone, Rachel Weisz and Marina de Tavira in the Best Supporting Actress category.
The 2019 Oscars will air live on ABC at 8:00 p.m. ET / 5:00 p.m. PT.