Loads of energy!
Harper, born in 1945, made an appearance as Master Bardell in a TV adaptation of The Pickwick Papers
in 1955 and did other child roles, but that wasn't to be his career.
He got a job as floor assistant on Doctor Who
in 1965 and worked his way up to be a director. There he directed The Caves of Androzani
and Revelation of the Daleks
, both considered classics. In 1993, he was slated to direct a 30th anniversary special called "The Dark Dimension", but this was axed before production began.
When it was announced that Harper would return to direct four episodes of series 2, there was much rejoicing. He directed all four of the Cyberman episodes. He directed three of the following season ("42", "Utopia" and "Last of the Time Lords", the last uncredited) and five of the season after that ("Planet of the Ood", "The Unicorn and the Wasp", "Turn Left" and "The Stolen Earth"/"Journey's End"), as well as the 2009 autumn special "The Waters of Mars". He did the Whatever Happened to Sarah Jane?
two-parter for series 1 of The Sarah Jane Adventures
and the two-parters The Temptation of Sarah Jane Smith
and Enemy of the Bane
for series 2. He has yet to work with Steven Moffat
. (Well, there was "Time Crash", but that was an eight-minute special.)
Harper has also directed episodes of other shows, including Robin Hood
and The Bill
The quote is his Catch Phrase
, saying something along those lines before every take.