The Brit boy band let loose before their show in Boston on Wednesday by jumping in a lake.
"Went swimming yesterday before the show in Boston. In a lake, in Boston," Harry Styles Tweeted.
The group's sound engineer David Martell even got in on the fun, sharing a photo of him swimming with Styles.
"So now the secret is out, me and @Harry_Styles went for a swim in the lake before yesterday's show in Boston. :-)"
After taking a dip, One Direction performed at the Comcast Center where they tried out their best Boston accents.
"It is an absolute pleasure to be here in BAWSTON," Styles told the crowd – which just ate it up.
– Megan Johnson