Captain Beyond is a one-of-a-kind progressive album with rock, heavy metal, and jazz influences with a "space rock" lyrical bend. Formed by former members of Deep Purple (Rod Evans, vocals), Iron Butterfly (Rhino, lead guitar, and Lee Dorman, bass), and Johnny Winter (Bobby Caldwell, drums) Captain Beyond is an album that flows from riff to riff, drumbeat to drumbeat, often with various time signatures within the same song. Taking a tip from the Moody Blues, songs flow directly into each other without benefit of any lag time between selections. Taken as a whole, the album is kind of a rush, as quick, riff-laden guitar lines predominate for a few songs before slowing down temporarily into a lull until the next takeoff.

Captain Beyond's second album must have confused the diehards. Where their self-titled debut had upheld the basic progressive heavy rock blueprint of lengthy instrumental explorations, constant tempo changes, and opaque, yet cinematic lyrics, Sufficiently Breathless downplays them for a subtler, song-oriented production. The predominant mood is snappy and businesslike; no track runs over five and a half minutes. This newfound conciseness certainly benefited such heavy-rocking efforts as "Distant Sun," even as the band stuck to their diverse guns on the moody, acoustic title track and the sleek Latin funk rock of "Bright Blue Eyes" and "Everything's a Circle." The results were intelligent and self-assured, yet the band's never-ending bad luck again intervened when vocalist Rod Evans quit in late 1973, leaving the album adrift. The band would proffer a markedly different style on their return four years later, but anyone dismissing progressive heavy rock as an oxymoron should definitely check out this album first.

Captain Beyond has a rather legendary status in the ranks of heavy prog '70s rock. Their fame is actually in the "cult status" category. Dawn Explosion, their third album, was a good disc, but really did not live up to the greatness of the first two releases. Still, in showcasing the group's unique blend of hard rock, psychedelia, and progressive-type arrangements, there is definitely some strong material present. The hard-edged and frantic "Icarus" and the nearly ethereal, building mini-epic "Breath of Fire (Part 1 and Part 2)" can arguably stand up to most of the material on the other releases. Where they falter here is on such songs as "If You Please" and "Midnight Memories," which seem to be trying to reach toward accessibility, but come much closer to banality and mediocrity. This disc cannot take away from the tremendous glory of the other albums, though, and several of the tracks certainly still hold up well.