A bowler takes three wickets in three different overs and it was a hat trick. How did this happen?

Answer 1:-

Though this sounds like a puzzle, this has actually happened in Test Cricket. 

This incident took place in Perth in 1988 when the West Indians toured Down Under.  In the 2nd Test, on the 3rd of December, Merv Hughes had Curtly Ambrose caught behind with the last ball of his 36th over. He removed Patrick Patterson with the 1st delivery of his 37th over to end the 1st innings of West Indies. This meant he had taken 2 wickets in 2 balls and was on a hat-trick. (He finished the innings with 5/130).

The Australians batted the remaining overs of the day and were bundled out the next day, i.e. 4th of December with a few overs for the day remaining. Once the 2nd innings of West Indies began, Hughes ran in to bowl with a hat-trick on and removed Gordon Greenidge off his first ball with an L.B.W. and completed his hat-trick. (He took 8/87 in that innings and finished with 13/217 in that game. He was awarded the Man of the Match award for his performance, though Australia lost the match by 169 runs.)

This hat-trick of his was completed, not only in 3 different overs, but also in 2 different innings and spread over 2 days. Interestingly, Hughes did not even notice that he had taken a hat-trick and had to be told about it.

Answer 2:-

According to ICC rule to count as a hat-trick three wickets must be taken in consecutive deliveries.

But all three wickets must be taken in the same match.

Now let us see how a hat-trick can be achieved in three different overs.

Test Match, 1st Innings.

Opposition score- 200/8.

Let us say Srinath is our star bowler and he has to achieve this feat of taking a hat-trick spread over 3 different overs.

55th over:
Srinath takes wicket on last ball of the over.Thus opposition is reduced to 200/9.

56th over:
 Will be done by some other bowler. No wicket falls in this over.Now Srinath comes back for 57th over.

57th over: 
Srinath takes wicket on first ball of 57th over.
Opposition 200/10. All out!

Srinath plays for India. So now India will bat.And after completion of India's 1st innings.Opposition will come to bat again in 2nd innings.

2nd Innings of Opposition. 

1st over: Our Star player Srinath bowls first over of this innings and take wicket on first ball. Three wickets in three balls taken.Hat-trick!

Thus a hat-trick can be taken by taking a wicket each in 3 different overs in a Test Match.