Pinnacle is an episode from series 23 that first aired on 4 July 2007.
When Tina Brogan, the charismac leader of an all-women group pyramid finance group, is found murdered in a field with banknotes jammed in her mouth. Her husband Terry, an alcholic, turns up at her home after an all-night bender. He can not account for his movements at the time of her death, and a pool of blood in his garage proves to be Tina's. Only Reid is convinced that Terry did not kill his wife, but more and more evidence mounts up against him - the grieving alcholic may not be all he seems.