The Irish comedian and actor was so keen to meet guest host Sean Hayes she refused to allow having nothing to wear get in her way - turning up in the slippers and a dressing gown from her hotel.
Bea, 38, shared photographs of herself on Twitter saying: "BA lost my luggage but luckily I was able to fashion an outfit for @JimmyKimmelLive from some items in the hotel. Just like Maria in the Sound of Music."
She added: "OBSESSED TO MEET @SeanHayes who was guest hosting this week. I had an excuse to touch him IRL, what a rush."
BA lost my luggage but luckily I was able to fashion an outfit for @JimmyKimmelLive from some items in the hotel. Just like Maria in the Sound of Music.
OBSESSED TO MEET @SeanHayes who was guest hosting this week. I had an excuse to touch him IRL, what a rush. pic.twitter.com/y7zZEtUlH3
— Aisling Bea (@WeeMissBea) June 22, 2022
The This Way Up star told Hayes: "The bags are just gone."
She added that after travelling for 22 hours she couldn't face the "thoughts of trying to find something."
Bea quipped: "Luckily, the hotel had this 'free dress' just lying in bathroom! I was like, I'll wear that."
The Doctor Who star is a strong advocate for sustainable and recycled fashion, regularly sharing with her Instagram followers the vintage and charity shop finds she wears to events and public appearances.
But she added she is desperate to be reunited with her suitcase.
She said: "Please, please just bring her home to me. We miss you, we love you, don't look in the back pocket."
As he welcomed Bea he asked her if she had expected the interview to be over Zoom.
She joked: "I wasn't sure if you'd notice, but I suppose I have to address it."
Bea has found fame in the US since starring opposite Paul Rudd in Netflix comedy Living With Yourself.
Her own Channel 4 comedy drama about mental health This Way Up is available to watch in the US on Hulu.
And she played the mother in recent Home Alone sequel Home Sweet Home Alone.
British Airways have not yet responded to Bea's tweet about losing her luggage.
Watch: Aisling Bea explains how miming made her career