Dennis "Denny" Crane is a fictional character on the television series Boston Legal. He first appeared during the final season of The Practice, and is portrayed by William Shatner.
Denny is a founding partner (and was chief rainmaker) of Crane, Poole & Schmidt, along with Shirley Schmidt and Edwin M. Poole. In his prime, he was a legendary litigator; his reputation amongst lawyers is long and fabled, and Denny himself insists he is the greatest lawyer in history and has never lost a case, stating that his record is 6,043-0. ("Loose Lips") This record is debatable, however, as Denny shifts the blame away from himself in lost cases he was involved with, saying that it was, in fact, his colleague who lost, not him. Paul Lewiston once observed that Denny is like Muhammad Ali late in his career, relying more on his past reputation than his current skills.
On a case involving seniors and prescription drug prices, Denny forgot the details of the case, and gave an opening statement that resulted in a mistrial to his client's benefit. He then finally took seriously Alan Shore's suggestion that he might have Alzheimer's Disease, and went to get tested for it. Later, Denny admitted to Alan that he had been taking a type of amphetamine drug to help him focus on trial procedures and stopped taking the drug. After trying a case involving the safety of red meat, he came to believe that his condition was due to mad cow disease, which he simply refers to as "mad cow." When Denny received his annual CT scan during the Christmas episode, a doctor revealed that Denny has mild cognitive impairment, which could be the result of normal aging or the early stage of Alzheimer's, and added that based on MCI patient history, Denny has an 80% chance of having Alzheimer's in six years. In the fifth season Denny begins to believe he is slipping. He makes an illegal bet with Alan over a case Alan has taken, and unintentionally reveals it to a the judge's clerk, nearly causing Alan to lose. Denny is disturbed by his memory lapse despite Alan's insistence that he is not slipping. At Shirley's Thanksgiving Dinner in "Thanksgiving" his mind slips, with Denny seriously believing for a moment they are gathered to celebrate his birthday, demonstrating to his coworkers the progressing severity of his condition.