Towards the end of 2005, Mike was diagnosed with Alzheimer's disease, aged 63. He soon split from his beautiful girlfriend Penny King (Pauline Fleming), whom he had intended to marry. He once asked Rita Fairclough (Barbara Knox) how her husband Len (Peter Adamson) was - when he had in fact died more than 20 years ago. He also went into The Rovers Return and asked where Bet Lynch (Julie Goodyear) was, not remembering that she had left the pub 10 years earlier. A further misunderstanding caused him to become estranged from Adam. Danny engineered sole inheritance of Mike's empire, egged on by his girlfriend Leanne Battersby (Jane Danson).