Megan Fox & Zac Efron's Dinner Date

If hotness was truly an explosive quality, this twosome might have been in danger of causing a bit of bang: Megan Fox and Zac Efron went out for an intimate dinner Tuesday night at Pace in L.A., Celebuzz reports, immediately starting up the relationship rumor mill.

A fellow diner revealed, "They were very friendly and their faces were close when they talked."

The two flirted back in January at the Golden Globe Awards, and Megan said recently that she considers herself single.

It could be a case of just friends, however, as OK! recently reported, Megan spent a weekend with on-again-off-again boyfriend Brian Austin Green, and Zac has been loyal to girlfriend Vanessa Hudgens for years.

Only time will tell if this super-hot duo will team up for the title of Hottest Couple Ever.