There are many different intertwining relationships in this play of deception and redemption. One of the main relationships that is emphasized is the relationship between a father and a son. This could relate to King Henry and Prince Hal, or Falstaff and Prince Hal, or King Henry and Hotspur.
King Henry and Prince Hal:
King Henry is very disappointed in his son because Hal spends all of his time hanging out at the pub with all of the pub crawlers. He does not act in a royal manner and causes trouble for his father. In the end Prince Hal reveals his plan to finally leave all of his bad qualities behind and take up the responsibility of being royal. In doing so he thought that he would seem even more respectable when he would become king because the people would not know what to expect. In doing this he renews his relationship with is father and ends up saving him during the battle. He kills Hotspur and gains the respect of his father.
Falstaff and Prince Hal:
Falstaff acts almost like a father figure or mentor to Prince Hal. They have an interesting relationship where the play jokes on each other and make fun of each other. One time Hal decided to play a trick on Falstaff and rob him and then make fun of him afterwards. This childish relationship reflects both Falstaff and Prince Hal's qualities and reveals to Prince Hal how he really should act if he hopes to become king.
King Henry and Hotspur:
King Henry at one point says that he would rather have Hotspur as a son and that he is more worthy of the throne than Prince Hal.
"Yea, there thou mak’st me sad and mak’st me sin
In envy that my Lord Northumberland
Should be the father to so blest a son—
A son who is the theme of honour’s tongue,
Amongst a grove the very straightest plant,
Who is sweet Fortune’s minion and her pride—
Whilst I, by looking on the praise of him
See riot and dishonor stain the brow
Of my young Harry. O, that it could be proved
That some night-tripping fairy had exchanged
In cradle clothes our children where they lay,
And called mine Percy, his Plantagenet!"
Act One Scene One Lines 77-88
In the beginning, Hotspur does like King Henry and is willing to help him, but throughout the play, he increasingly begins to use King Henry's affection to his advantage. King Henry never expected that Hotspur would turn against him or betray him. Hotspur uses this knowledge to gain his trust and then in the end rallies the rebels against him to overthrow his reign. King Henry realizes that he should not be so trusting of others. He sees that his own son was in reality better than Hotspur could ever be.
Throughout the play the relationships between the characters changed and ultimately revealed who they could really trust.