Answer: A Llama

In the early 1980s, Michael Jackson and Queen singer Freddie Mercury planned a collaboration. They initially recorded three demo songs in Jackson’s home studio, and later met up to record the complete project at a fully equipped studio.

The project never came to fruition and, officially, the reason given was time constraints and conflicting schedules: both performers were, after all, quite busy around 1983-84 when the collaboration was taking shape.

Unofficially, however, the problem was a…llama. Years after the fact, Queen’s manager Jim “Miami” Beach explained in a London Times interview that Jackson had brought his pet llama, Louie, to the studio and refused to record without it. Mercury called up his manager and explained “Miami, dear, can you get over here? You’ve got to get me out of here. I’m recording with a llama. I’ve had enough and I want to get out.”