A White House photo of President Obama and and child dressed as Spider-Man has attracted a lot of attention this week, and NBC's Jimmy Fallon sought on Thursday to explain exactly what was going on in the picture. 

"Obama was like, 'Shouldn't you be fighting the Green Goblin?' While the kid was like, 'Shouldn't you be working on the fiscal cliff?'" Fallon said in his monologue on "Late Night with Jimmy Fallon."

"Actually, the kid was really excited to meet the president, while [Vice President] Biden was really excited to meet Spider-Man," he added. 

Check out the joke below.