With shiny new bikes, Rain and Hong-chul kick off their adventure on a rainy day in Jeju Island. Locals Lee Hyo-lee and Lee Sang-soon join for dinner.

The pals cruise along Jeju's emerald-colored coast and flower-lined roads. The loser of a vote on whose bike is cooler faces a fish-tastic punishment.

A hands-on experience of Gochang's natural treasures awaits, from rock climbing and clamming in the mudflats to a breathtaking sunset ride on the beach.

Zipping through Busan on Harley-Davidsons, the friends stuff their bellies with local specialties. Later, they place a bet on who's the better swimmer.

Bad weather can't deter Rain and Hong-chul from enjoying the perfect beach day. Once the clouds clear, the pals soak in some fun and sun on a yacht.

The pair zooms through the lush, winding mountains of Gangwon-do for a camping trip. To Rain's embarrassment, Hong-chul becomes his stylist for the day.

Historical Gyeongju offers a hearty breakfast and plenty of sightseeing. Reminiscing about their younger days, the duo gets silly at an amusement park.

Riding on Triumphs through stunning Namhae by the sea, the friends visit an impressive bike gallery and catch epic ocean views at every turn.

Back in Jeju Island, Hyo-lee and Sang-soon bring the duo to the recording studio. And in Seoul, their journey closes out with a welcome surprise.