Michael Joseph "Brian" O'Kelly FSA MRIA[1] (5 November 1915 – 14 October 1982)[2] was an Irish archaeologist who led the excavation and restoration of Newgrange, a major Neolithic passage tomb in the Boyne Valley, County Meath, Ireland, now a UNESCO World Heritage Site.

He was inspired to take a new career path, and in the autumn of that year, he switched courses at university again, this time to archaeology, becoming one of Ó Ríordáin's students.

[4] The couple had three daughters, including the Germanist scholar Helen Watanabe-O'Kelly, and lived in Blackrock, Cork.

[2][5] In 1946 O'Kelly succeeded Professor Ó Ríordáin as head of the Archaeology Department at Cork, a position he held for 36 years.

On 21 December 1967 O'Kelly confirmed a local legend that the rays of the sun on the midwinter sunrise go straight through the tomb – passing through a small 'roof-box' opening above the doorway to penetrate along the whole length of the passage as far as the center of the chamber.

To ensure this, the builders took special precautions to make sure the tomb stayed completely dry, as it is to this day.