Terry Gilliam's films have always been for me, a little like dropping dried peas off a bridge in to a jar. Sometimes you know when one falls in to the jar you'll get a satisfying ringing sound, but mostly they'll miss with some inevitable disappointment which can only be quelled with either alcohol or further pea dropping.
They either hit or miss, and this thankfully is a hit.
In a nutshell this is a classic 'wager with the devil' sort of film (the Devil or Mr Nick is played by Tom Waits). Dr Parnassus (Christopher Plummer) is an immortal who makes a wager with the Devil. I won't go in to the plot too much as it is just a meditation and not a proper review.