I had the opportunity a few months ago at Robert McKee's genre seminar to meet John Cleese (one of my comedy idols). Happy to report that Cleese is working on a new screenplay and he's also working on a musical adaptation of A FISH CALLED WANDA.
Cleese mentioned his life changed when he saw BEYOND THE FRINGE being performed at the West End. FRINGE was recently released on DVD and I suggest you look for that. Cleese would later work with Peter Cook -- the prime writer of most of the FRINGE material.
Cook was an absolute comic genius. He created a unique style by blending the lunacy of the GOONS with the British public school sensibility throwing in a dash the absurdism of Lewis Carroll and bringing to a delightful cornucopia of comedic flavors by tossing in a cornucopia.
Cleese and Cook would work together in a special entitled PETER COOK AND COMPANY. Cleese said this bit (and I apologize in advance for the poor quality but it's the only one I could locate) was not well received at the time. I told him it was a classic, absolute genius, and then dropped several more names, which he was kind enough to help me pick up from the carpet.