"Jammin' with Jeff. It's a day off. So we've been singing a bunch of old songs. Jeff won't practice, so it's first go or nothing. @jeffgoldblum makes me laugh immoderately. He is also a prodigy," Neill captioned their duet of "A Fine Romance."
A second Instagram video of the actors singing "I've Grown Accustomed to Her Face" was accompanied by the message: "Jeff Jammin' More from the #LoungeGoldblum on this day off. Next time I will wear my shades too. I had a cool deficit ... @jeffgoldblum."
Neill, 72, and Goldblum, 67, are in Britain filming the sixth chapter in the franchise -- Jurassic World: Dominion.
The dinosaur adventure, which is set for release in 2021, was shut down for months because of the coronavirus pandemic and became one of the first major Hollywood productions to resume filming this summer.