The trip captain leads the group on the final, and most treacherous, ascent. But the trail still has a few surprises in-store for the group

As the group gets closer to Phantom Lake, one rider has to lag behind due to mechanical issues, while the trip captain has to confront an unexpected guest.

Unexpected roadblocks leave the goal of reaching Phantom Lake in jeopardy, pushing the trip captain to offer a hard choice to the remaining riders.

It's now or never. The trip captain pushes the crew to their limits in hopes of reaching the summit of Corkscrew Pass.

The remaining riders take their bikes onto Ophir Pass for the first off-road, and most challenging, ride yet

Before the sun sets on the second full day of riding, one rider will be sidelined, a tragic accident will put the life of another in jeopardy, and the group will be forced to make some hard decisions.

The crew lands in Denver to begin the grueling ride to Phantom Lake-and from the start, things go sideways. Mechanical challenges sideline two bikes, while stress pushes another ride to the edge, forcing the trip captain to make a difficult decision.