Calvin Harris became one of EDM-pop's most successful architects with 18 Months, which fused the dance style's drops and fizzy highs with radio-friendly hooks.

He doubles down on that approach on Motion, which features even more stylized songs and cameos from A-list singers.

However, the album's finest moment belongs to Harris alone: on the former hit single "Summer," he uses EDM's dramatic peaks and valleys to convey the fleeting high of a summer fling, while the craggy warmth of his voice -- the last remnant of his more idiosyncratic electro-indie days -- adds some much-needed humanity and personality.

Elsewhere, Motion lives and dies on the strength of Harris' collaborators.

As on 18 Months, which was anchored by mega-hit partnerships with Rihanna ("We Found Love") and Ellie Goulding ("I Need Your Love"), many of this album's highlights feature female vocalists.

Harris' reunion with Goulding, "Outside," doesn't quite recapture the magic of their previous work but does make the most of her deceptively powerful soprano, this time in a more upbeat setting.

Likewise, "Pray to God" showcases HAIM's fetish for mainstream '80s sounds, channeling Stevie Nicks' "Edge of Seventeen" with its lavish harmonies, chugging guitars, and sizzling hi-hats, while "Together" dresses Gwen Stefani's playful, confident pop in EDM drag.

Moments like these prove that Harris' formula doesn't have to be formulaic, but unfortunately they're few and far between.

Despite, or perhaps because of, the many personalities involved, the album feels more than a little faceless.

John Newman even sounds a little like a more bombastic version of Harris on "Blame," while "Open Wide" capitalizes on Big Sean's put-upon lothario persona but ultimately fizzles.

Motion's instrumentals also suggest that Harris' machine might be a little too well-oiled; tracks such as "Overdrive" and "Burnin'" are so quintessentially EDM that they're almost parodic.

At best, they sound like they're waiting for vocals to complete them, and at worst, their buildups and breakdowns are so predictable listeners could set their watches to them.

Despite a few bright moments, Motion is disappointingly bland -- especially since Harris has made plenty of memorable electro-pop before and after his EDM makeover.