After crossing one of Iris' rainbows, Chris and Martin switch bodies and slowly start switching personalities as well! Will they find a way of returning to normal before they lose each other's true selves?
After a storm passes while the Wild Kratts were at The Park, a rainbow appears. Mina said that even though there isn't gold at the end, her Aunt Iris always leaves something there. The crew decides to race to the end. The Kratt Brothers are neck-and-neck as they run down the hill, but Chris trips over a rock and pulls Martin down with him. The two roll down in a ball until they are sent flying by a ramp like rock and fly through the rainbow. They tumble for a bit before stopping in the grass on their backs.
"That... wasn't part of the plan."
- Martin(?) agreeing with Chris(?)
They realize that they weren't talking in their respective voices so they look at each other. Chris had Martin's blue eyes and signature blue and Martin had Chris's hazel eyes and signature green. The brothers scream in panic. They had switched bodies.
Back in the Tortuga, Maris (Martin/Chris) and Chritin (Chris/Martin) were pacing in panic until Luna came in with details from Iris. She explained that the goddess of the rainbow said that their current situation wasn't the first that happened and that she leaves an hourglass at the end of her rainbows in case it does happen. The hourglass counted down the hours that the sun is up. The brothers will have to cross another rainbow in that amount of time before all the sand is at the bottom or they'll be stuck in each other's bodies forever. She assures them that any rainbow made through refraction will work. Aviva tells the bros that until they find a rainbow, they have to pretend to be each other around any others.
During training, their respective medallions weren't working. Mina theorizes that it's because they're not in the right bodies and to try swapping medallions. The don't get the hang of each others' powers at first: Maris got a headache from thinking so much, but manages to make a vine grow a foot, and Chritin instantly moves the water, but no control and it splashes into Koki. Maris tells his brother to be careful about what he thinks because his powers react more to emotion than thought and Chritin tells him to take it slow. After those tips, the get the hang of their temporary powers.
Meanwhile, Zach decided to spy on them and is surprised that the brothers swapped colors. He sends in a Zachbot to hear their conversations and and discovers what happened to them. He then plots to make sure they don't switch back.
Several hours later, the swapped bros are walking in The Park.