• Prince Harry's book Spare comes out on Jan. 10
  • A leak from The Guardian previewed shocking details
  • Harry will allege Prince William assaulted him a few years ago

Prince Harry's new book has been all the talk lately, with the royal making serious allegations against his family ahead of its release.

And it looks like he plans to tell all – for real – in Spare. The book comes out on Jan. 10, but The Guardian has previewed several bombshell reveals days in advance.

The big one? That Prince William assaulted Harry in 2019 during an argument over his wife Meghan Markle.

Report: Prince Harry describes violent incident with William

Per The Guardian, Prince Harry will allege that at the height of the argument, William "grabbed me by the collar, ripping my necklace, and he knocked me to the floor." 

William apparently "urged him to hit back," but Harry refused. William apologized soon after, but he encouraged Harry not to tell Meghan about it.

According to The Guardian, Prince Harry recalls telling his brother, "You mean that you attacked me?" To which William replied, "I did not attack you, Harold." 

Also interesting:

Harry reportedly says the incident left him with "scrapes and bruises," plus cuts from a bowl he landed on when William knocked him over. 

Some pretty serious allegations. It's the first major leak from Spare, which drops on Jan. 10, 2023. We'll see if the future King issues any response...

See more in the video above.