He began with three close wins before scoring 126 against Stewart Scott – the highest score of the series so far. He followed this up with 96, 103 and 100 in three more winning performances. In his 8th game, he faced Garvin Loughrin and went into the conudrum trailing by 82 to 85, however it was Macdonald-Cooper that got the conundrum in 2 seconds and became an octochamp. He qualified for the finals as #2 seed with an octotal of 780 points, but lost in the quarter-final to #7 seed Peter Davies. Davies beat him in the first two numbers games and with the words POIGNANT and RAVAGES which were enough to ensure him a 83 – 67 lead going into the conundrum, which Macdonald-Cooper would solve.
Away from Countdown, Macdonald-Cooper has been heavily involved in crossword puzzles. He has won two crossword-solving championships, one in 1984 for the Observer's Azed puzzle, and the Times Crossword Championship in 1991. He has written crosswords as Calmac and Spurius, and was the Independent's crossword editor between 1998 and 2005.
In 1986, he was a semi-finalist on the BBC quiz show Mastermind.
|#||Date||Type||Contestant 1||Score||Contestant 2||Guest||Lex||Max|
|4513||8/01/2008||P||Grant Watson||70 – 87||Michael Macdonald-Cooper||Roger Cook||Alison Heard||121|
|4514||9/01/2008||P||Michael Macdonald-Cooper||92 – 65||John Brewster||Dr Phil Hammond||Alison Heard||118|
|4515||10/01/2008||P||Michael Macdonald-Cooper||84 – 73||Karyn Cooke||Dr Phil Hammond||Alison Heard||116|
|4516||11/01/2008||P||Michael Macdonald-Cooper||126 – 29||Stewart Scott||Dr Phil Hammond||Alison Heard||148|
|4517||14/01/2008||P||Michael Macdonald-Cooper||96 – 49||Jason Meek||Dr Phil Hammond||Alison Heard||130|
|4518||15/01/2008||P||Michael Macdonald-Cooper||103 – 88||William Bailey||Dr Phil Hammond||Alison Heard||121|
|4519||16/01/2008||P||Michael Macdonald-Cooper||100 – 41||Howard Salinger||Alastair Stewart||Alison Heard||119|
|4520||17/01/2008||P||Michael Macdonald-Cooper||92 – 85||Garvin Loughrin||Alastair Stewart||Alison Heard||119|
|4622||13/06/2008||QF||Peter Davies||83 – 77||Michael Macdonald-Cooper||Alastair Stewart||Susie Dent||123|