But they weren't by each other's side for long…
"I lost him so he's not being the best boyfriend right now," Cyrus quipped to me on her way into the Arclight Hollywood Cinema. "The whole deal was we were going to be walking together, but then I lost him first thing because he started saying hello to everyone."
Hemsworth, dressed in Calvin Klein, joked that life has gotten a bit tougher ever since Cyrus confessed to Ellen DeGeneres that she fell for him after he opened a door for her.
"There's so much pressure for me to be opening doors for everyone now," he said. "It's just too much pressure."
Hemsworth is still adjusting to the attention. As I first told you about, he got a lot of attention during a trip earlier this week to Toronto to promote the flick. Female fans chased after him when he left a special screening there, among other things.
"That was my first experience of the craziness," he said. "It's totally flattering, but funny, too."
Next stop on the Last Song tour is Europe with premieres next month in London, Rome and Munich.
Also making their way on the carpet tonight were Cyrus and Hemsworth's costars Greg Kinnear, Kelly Preston, Carly Chaikin, Melissa Ordway, Hallock Beals, director Julie Anne Robinson, writer Nicholas Sparks and producers Adam Shankman and Jennifer Gibgot.
That's not all I have for you from The Last Song premiere. Make sure to keep coming back right here for more.
Find out what The Last Song director Julie Anne Robinson had to say about working with Miley Cyrus here.