The dancers all drop hands and the center dancers step forward, while the end dancers don't. At the same time they all turn 1/4 toward the center of the line, adjusting their position so that they are facing a dancer from the other half of the line. They then do a right pull-by with that dancer.

Everybody ends back to back, with the other person from their half of the original line as their partner.

Note that Explode the Line is a generalization of Explode the Wave. It is most commonly used from a one-faced line, but it works from any kind of line (including a wave). Similarly, the prefix Explode and can be used from any kind of line, with the dancers doing the named call after adjusting to be facing couples in the same way.