Jason Donovan cycled to Hyde Park to reunite with Kylie Minogue on stage during her headline show in London.
The singer was top of the bill at BBC Radio 2 Live In Hyde Park on Sunday, where she performed their 1989 duet Especially For You.
Midway through the song, she said "Well now, I need a dance partner" and her former Neighbours co-star Donovan came out on stage to pick her up and spin her around.
Author Katy Lette, who was at the concert, shared a photograph of Donovan on his bicycle on social media, writing: "Gotta love an earthy, no fuss Aussie."
She added: "The lovely #JasonDonovan cycled to Hyde Park for his stage duet with Kylie Minogue last night. She’d only called him an hr earlier."
Donovan also wrote: "I literally turned up on my bike to support my friend Kylie Minogue and next thing you know I’m onstage Hyde Park in front of 70,000 people recreating those dance moves Especially For You 1988 .. mad!
"Loved every second. Thank you for all your support. Memories = magic," he added.
After performing versions of Golden, Spinning Around, It’s In Your Eyes and Can’t Get You Outta My Head at the show, Minogue was joined by a gospel choir for Especially For You.
After Donovan twirled her around on stage and the pair embraced, she told the audience: "Where do we go from there? I had no idea that was going to happen!
"Thank you Jason. We travelled back in time there."
Continuing with her back catalogue, she also delighted fans with renditions of Locomotion and I Should Be So Lucky before she was joined by Rick Astley to sing his hit Never Gonna Give You Up and Kids, the duet she originally released with Robbie Williams.
Minogue, who celebrated her 50th birthday in May, said both Donovan and Astley had been at her party to mark the occasion, adding: "50 happened this year and for more than half of those years I’ve been with quite a lot of you."
She went on to thank her fans for sticking with her through "the ups, the downs, the middle of the road, the got it right, got it wrong".