Metzler co-directed the John Waters' narrated documentary, Plagues & Pleasures on the Salton Sea,[6] with Jeff Springer which premiered at the 2004 Slamdance Film Festival.

In 2010, he completed the Emmy nominated documentary film, Everyday Sunshine: The Story of Fishbone, co-directed with Lev Anderson and shot and edited by Jeff Springer.

[8] His most recent theatrically released film, co-directed with Quinn Costello and Jeff Springer, is the ITVS funded documentary Rodents of Unusual Size (2017) about giant invasive swamp rats, nutria threatening coastal Louisiana and is narrated by Wendell Pierce.

The style and offbeat subject matter of Metzler's work is heavily influenced by filmmaking predecessors such as Errol Morris and Les Blank.

Cinéma vérité ('truthful cinema') is a style of documentary filmmaking, invented by Edgar Morin and Jean Rouch, inspired by Dziga Vertov's theory about Kino-Pravda.