It all started with a ridiculous idea and zero hesitation. The plan? Ride a recumbent bike—yes, one of those laid-back, low-to-the-ground contraptions—on the rugged terrain of Red Bull Rampage ...

It's the morning of Christmas Eve and Phineas and Ferb are shown flying through the air on the "dual toboggan" beds. Meanwhile, Candace is in her room, talking to her mom on her cellphone. Linda and ...