You know how in musicals when one person breaks into song, in a casual situation, and EVERYONE around them knows the routine? Well, flash mobs are pretty much that but IRL.

To celebrate new MTV show'Say It In Song', we've put together the biggest and best flash mobs from all over the internet.

Be prepared to feel ALL the feels when watching these...

1. The Lion King Australia Cast Singing 'Circle Of Life' ON A PLANE!

THAT KEY CHANGE!

2. This Downtown Disney Flash Mob Proposal

We're definitely not crying. Nope. There's just something in oureye.

3. These Teachers Flash mobbing An Assembly With 'Let It Go'

Who doesn't love a Frozen sing-a-long?

4. T-Mobile's Train Station Flash Mob

Okay, we know it's for an advert but we still love the look on all the bemused commuters' faces.

5. This Micheal Jackson Tribute In Stockholm

You can't go wrong with a Micheal Jackson tribute!

6. These 'Single Ladies' In London

You know what's better than one Beyoncé. 100 Beyoncés. Ultimate #SquadGoals.

7. And finally, the best movie flash mob of all time

Joseph Gordon-Levitt + dancing + amarching band = movieflash mob GOLD!

Love a flash mob? Make sure you tuneinto our brand new show'Say It In Song', hosted by Redfoo,which starts at 8pm on Monday (August 3)on 'MTV'.