A team of 6 contestants play a series of physical, mental, skill and mystery games across 4 themed zones gaining as many crystals as possible which determine how many seconds they get as they attempt to win a prize inside the Crystal Dome.

Phineas et Ferb inventent, manigancent et gardent une longueur d'avance sur leur peste de soeur. Pendant ce temps, leur ornithorynque de compagnie élabore des complots contre le diabolique Dr. Doofenshmirtz.