Warthur One of the reasons "Christian rock" is often such a turn-off is the shallow pool of themes some of its practitioners draw on. What, you have a thousands-year-old tradition of philosophy and religious imagery and stories and history to draw on, but you keep writing songs on the same narrow themes of "you should accept Jesus" and "sin is bad, you should abstain from it"? Come on, now.

This is why it's heartening to find Neal Morse, on "?", tackling a more obscure concept: this is a concept album based around the Tabernacle In the Wilderness, the temple-in-a-tent which in the Biblical story the Israelites use as their place of worship until the wanderings of Exodus come to a close and the Temple in Jerusalem is built. This certainly makes a refreshing change from his previous two prog-oriented solo albums, Testimony and One, the former of which told his own conversion story and the latter of which told the much more familiar tale of the Prodigal Son (and is therefore, really, another conversion story).

It probably helped that 2005 also saw Neal branching out a little when it came to his output of Christian-themed music: between his singer-songwriter release God Won't Give Up and the first of his long-running Worship Sessions series, he was producing a fair amount of straight-ahead Christian music. Clearly he wasn't abandoning prog - after all, he put this out in the same year - but it meant his impulse to share his religious convictions had several different outlets, which meant he could use his worship music releases for his direct and uncomplicated declarations of faith and use his prog releases to explore subject matter better suited to a nuanced, epic-length exploration.

Certainly, his creative batteries seem to have been firing here: whilst much of One was co-written with Randy George and Mike Portnoy (who return here to once again provide a consistent rhythm section across the whole album), this time around the album is almost all Neal's own work in terms of compositions, with the exception of The Outsider. He's restrained his impulse to make epics this time, but only kind of: you could see the album as one 56 minute piece with a bunch of different sections, or a prog opera of 12 pithy songs.

As with One, the core performers of Morse, George, and Portnoy form the nucleus of a revolving band of musicians, which this time around includes a particularly interesting range of guitarists. As well as the great Steve Hackett, Morse also gives a bit of guitar spotlight time to his brother and Spock's Beard co-founder Alan Morse, and to his Transatlantic crewmate Roine Stolt (leaving the album just a Pete Trewavas away from being a Transatlantic reunion).

As shocking as Neal's departure from Spock's Beard and Transatlantic was to the prog world at the time, history would prove that those bridges weren't burned in the long run - Transatlantic would reassemble by the end of the decade, and Neal has made occasional guest appearances both live and in the studio with Spock's Beard, as well as returning to the band for a one-off live performance of Snow; having Alan and Roine on the album was therefore a sign of things to come.

With such a stellar range of guitarists offering their talents, it's no surprise that there's a good range of solos showcasing their individual styles, and perhaps it's the guitars that are the star players here, though the musical backing is diverse enough that it's not 100% a guitar album. Jim Hoke offers some great saxophone lines, for instance, and whilst the style is mostly influenced by classic prog there's some trip hop-esque drum fills here and there; Portnoy's Dream Theater/Liquid Tension Experiment compadre Jordan Rudess also swings by to contribute on keyboards.

All in all, it's another application of the same Neal Morse approach he's followed on his prog releases ever since the earliest Spock's Beard albums: lots of influences from classic prog, sunny disposition, not afraid to throw in a few influences from musical styles outside the usual prog palette to keep things spicy.

Perhaps the biggest departure here is the length - or rather, the restraint displayed with respect to it. Weighing in at a bit over 56 minutes, this was the first time one of Neal's prog-oriented albums (whether solo, or with Transatlantic or Spock's Beard) had come to less than an hour's length since The Kindness of Strangers. The music world in general went through a bit of a phase in the late 1990s and early 2000s where people wanted to cram CDs full to the brim, which often led to a bit of filler; here Neal seems to have realised (as many other artists were realising at the time) that it's better to offer 50 minutes of really solid music than 70 minutes of quite good music.

Between this and the way the album seems to have an extra shot of energy or playfulness to it - more than I can remember hearing on Testimony, or One, or for that matter Spock's Beard's Snow - I think "?" established a new tier of quality in Neal Morse's solo prog output.