The Stainless Steel Rat Sings the Blues

This is the third prequel to the original book, and was quite disappointing. The good points are the setup (Jim DiGriz forms a musical group to infiltrate a prison planet) and how quick it is to read.

The prison planet itself contains a multitude of societies, each less believable than the one before. One of these is clearly Harrison's clumsy commentary on Robert Bly's book Iron John.

Having now read all three sequels, I would recommend stopping after the first one.