After toiling for just one wicket in 42 overs at Lord's in the drawn first Test, Plunkett snared three of the top four batsmen to put England in control.
Sri Lanka won the toss and batted under clear skies although the ball moved around throughout the session.
Matthew Hoggard gave England the perfect start when he bowled left-hander with an inswinger for a duck with the fifth delivery of the morning.
Skipper Andrew Flintoff then removed himself from the attack after he had conceded nine runs from just three overs and introduced the 21-year-old Plunkett. It proved an inspired change.
A confident appeal from the second ball for caught behind was rejected and replays showed umpire Aleem Dar had made a shrewd decision as the ball had flicked Michael Vandort's shirtsleeve.
However off the next delivery, Vandort (9) drove loosely at a wide and full delivery. Paul Collingwood lunged to his left and held on to a fine catch in the gully, justifying his reputation as England's best fielder.
Vandort had been included at the expense of Jehan Mubarak, who played in the first Test, and former skipper Sanath Jayasuriya, who has come out of retirement.
The final ball brought the biggest cheer when Sri Lanka skipper Mahela Jayawardene edged his third delivery to wicketkeeper Geraint Jones and departed without scoring to complete a double-wicket maiden.
After Jayawardene's 61 and 119 at Lord's, it was a wicket met with understandable jubilation by the England players with Sri Lanka now 16 for three.
Five overs later Hoggard claimed his second wicket when Thilan Samaraweera (3) deflected an outswinger to the reliable Collingwood at fourth slip. Sri Lanka were in deep trouble at 25 for four.
The score was almost 36 for five when new batsman Tillekeratne Dilshan, on two, was caught low down by Flintoff but umpire Dar called no-ball after Plunkett had overstepped.
Kumar Sangakkara became the penultimate wicket when he edged a Plunkett delivery angled across him to Jones. His hard-fought 25 runs had taken 87 minutes.
Jones completed his third catch when all-rounder Farveez Maharoof (5) edged Sajid Mahmood from the last ball before lunch.
The only flaw during a triumphant morning for England came when Maharoof was dropped on one by Andrew Strauss during Mahmood's previous over. Strauss spilled two of the nine England catches which went down at Lord's.