Sam only realizes that he's holding his breath when his vision begins to blossom with large black spots. He rasps in a sudden, large gasp of air and keeps on watching as the brightness around the door continues to increase, flickering tendrils of blue light slowly edging their way down the steel bands that cross the door in the very center, beneath the twisting lock.

The light reaches the mirrored crescents on each crosspiece... and stops advancing.

Hot red sparks begin to spit from the tips of each crescent as blue flame is transmuted to burning gold, a gold that's echoed in the metal of the pentacle lock-- which itself has stopped turning and is beginning to glow.