Writers don't pretend to be mathematicians, but even I know that four times four does not equal eight. You know what else isn't eight? Seven. 4x4=8, the "mini-musical" montage from producer John Oules and curator Mark LaPierre, turned out to be a mystery with one mini gone missing at Thursday night's Fertile Ground performance.

Inspired by the space constraint of Ten Tiny Dances, 4x4=8 uses limited props and a four-foot-by-four-foot stage to up the dramatic potential. Actors play out awkward teenage interactions, awkward adult interactions and the odd murder mystery to original compositions by Portland musicians and playwrights. This year’s production is a complete renaissance of its 2012 namesake; same concept, entirely different acts.

Mark LaPierre’s brainchild starts off the show with Sherlock Holmes in a quandary. Then things turn practical with Valery Lawrence’s piece on a couple in therapy for their bumpy relationship and Amber Kiara Mitchell’s peek into not-so-closeted teen angst. But the first act ends with a bang (or rather, a thud) in “Murder For All.” In the shortened second act Aubry Jessen’s time travel segues into William Sam Gregory’s travels to nowhere. And, bookending his own show, LaPierre closes it out with “Tech Booth,” a behind-the-scenes look at theater itself.

Despite the potential of a tiny stage, 4x4=8 fails to add up to anything extraordinary. There is variety of genre, music and theme, but what culminates is a grab bag of alternatingly enjoyable and mundane pieces. LaPierre undoubtedly steals his own show with the first and final self-reflective pieces, lifting the curtain and then breaking the box of theatrical dimensions. The show ends with actors shamelessly appealing for applause, but it’s done so amusingly and musically that we’re happy to comply.

Unfortunately, the spaces in between fall flat. Set in a closet, “7 Minutes in Heaven” feels a bit more like purgatory. With singing.  This is largely due to the lack of imagination in setting a small stage production in...a small space. In other cases, quiet singing is overwhelmed by its own music. Lawrence attempts to play with the unusual constraints by confining her couple to an imaginary car, but like all the daily life pieces, it fails to break out of the box. This is especially disappointing considering 4x4=8’s dance inspiration. As much as I hate to hand it to the Brits (even play-acted ones), only the Holmes opening and Anglo-inspired murder melodrama fully utilize their unique space.

Maybe the pre-show “no texting or sexting” jingle counts as musical No. 8? We’ll let the numerical faults slide. This is the arts, after all.