Two shows opened last weekend that seek to influence the debate on the upcoming marriage amendment. With "Love & Marriage," Illusion Theater presents an eclectic musical revue by Roberta Carlson and Michael Robins. "But Not For Love," by Matthew A. Everett, a co-production of The Flower Shop Project and Workhouse Theater, treats the subject as a romantic comedy.

In Everett's play, a brother and a sister are marrying the men of their dreams in a double ceremony. But there is a disagreement about whether this should be a private or a public event. Protestors show up, including the gay groom's brother. An older, widowed police officer finds himself attracted to the pastor, not realizing that she is a transgender woman.

The play is light, campy, frothy comedy. But an act of homophobic violence takes the story to a very dark place, before returning to a perfectly believable happy ending. It engages in a serious and thoughtful discussion of faith and values. Director Richard Jackson manages to keep all those balls in the air to create a satisfying whole.

As the two couples, Foster Johns, Jeremiah Stich, Paul Rutledge and Jen Rand are uniformly strong. But special kudos go to Carl Atiya Swanson as the angry brother, and to transgender actor Erica Fields as the pastor and Shawn Eric Hoffman as the cop, for their sweet burgeoning romance.

("But Not for Love" by Matthew Everett, directed by Richard Jackson. 7:30 p.m. Fri-Sat., 2 p.m. Sun., 7:30 p.m. Oct. 22, ends Oct. 28, $11-$15, The Warren - An Artist Habitat, 4400 Osseo Road, Mpls, 612-216-1583 or boxoffice@workhousetheatre.org)

"Love & Marriage" brings together a diverse variety of love songs, from comic show tunes to power ballads to the blues, from Rodgers & Hammerstein to Cyndi Lauper to Ray Charles. Staged with theatrical flair by Robins and sensitively accompanied by Carlson, the songs are presented in a variety of ensembles and combinations of singers, stressing the universality of love, across the orientations.

It's a pity there's no CD of these sterling performances by some of the most talented vocalists in town: Dennis Spears, Cat Brindisi, Charles Johnson, Rachel Hurst, Adara Bryan, Melissa Hart, Randy Schmeling and Reid Harmsen.

What elevates the evening is a juxtaposition of the music with video interviews with actual couples (same gender, mixed-gender, mixed-race), speaking with real candor and genuine hilarity. You couldn't write this stuff; it's the humor of real people.

These shows are the best kind of political theatre. They don't beat you over the heads with their positions. They reach out to touch and transform the heart.

(Illusion Theatre, "Love & Marriage" by Roberta Carlson and Michael Robins, directed by Robins. 8 p.m. Thu.-Sat., 7 p.m. Sun., 10 a.m. Oct. 24, ends Oct. 28, $15-$28, Cowles Center, 528 Hennepin Av., Mpls., 612-339-4944 or www.illusiontheater.org)