I was trying to do something else, but when I arrived here I thought it was fun enough to post.  I hope you have fun too!

Ross

Who is Irene?  ^^

got it on the first try, it was an easy one, but very nicely done

i don't know who this irene person is but  i will admit i had to look at the solution.

Nice one, thank you!

Apart from your solution, which takes four moves, there is one in three moves. I will give it in white colour, to view it, please mark the text below this:

1.Qxd4+ Qd6 (1...Qxd4+ 2.Rxd4+ Bxd4+ 3.Rxd4#) 2.Qxf6+ gxf6 3.Rxd6#

There is a forced mate in 3 without even using the knight fork on the queen too. 

• QxP... QxQ
• RxQ... BxR
• RxB mate.

You could also play RxP (either one) first.

So I didn't solve the puzzle, but I got the king one move faster :p

Easy

After QxP, the black Queen has the option of d6, the white queen is pinned by the black bishop and both queens are lost.

Ross

"Good night Irene" is an expression used in our locality--it us usually best used with liberal rolling of they eyes and slapping of the forehead.  It is probably interchangeable with "Good grief Charlie Brown."

The reason I named this puzzle "Good Night Irene" was because it made good use of both knights, and so it was supposed to be a little clue (not that the puzzle needed clues, but the phrase/pun struck me as catchy.)

3. ... Ne6# as well as Qe7# are nice finishing moves too... good one.

i'm glad my name isn't irene.

It's a song.

1 Qxd4+ Qd6 2 Qxf6+ gf 3 Rxd6+ Ke7 4 Rd5 mate also works.