Just a few weeks after winning the IBF world welterweight title last August, Brook was attacked on the final night of his holiday with his family on the Spanish island of Tenerife. The reasons for the attack are unclear, but Brook said he was slashed through a muscle by a knife resembling a machete, and was left to die.
Brook underwent emergency surgery and was given a blood transfusion. Now, six months later, he will make the first defence of his title in his home town of Sheffield in northern England, on Saturday.
"I'm here with a smile on my face," the 28-year-old Brook said, "because I've got a second chance."
Brook's opponent is mandatory challenger Jo Jo Dan, a Romanian who has lived in Canada since 2003 and recently received Canadian citizenship. Dan has won 34 of his 36 fights and never been stopped.
Brook is already looking ahead to a potential fight with Floyd Mayweather Jr.
Brook is in the same star-studded division as WBA and WBC champion Mayweather and WBO champion Manny Pacquiao, who meet in Las Vegas on May 2. Brook thinks Mayweather will win "convincingly," and wants a unification fight.
"On May 3, there will only be two men in the division with world title belts. I would love to do a unification with the winner," Brook said. "I do belong at that level. I know at 100 per cent I will beat any fighter."
Brook has won all 33 of his fights, the last being against previously unbeaten Shawn Porter in a majority decision in Los Angeles.
That was Brook's second fight outside Britain and he wasn't widely known outside boxing circles. This weekend, he is back home and now regarded as one of Britain's top fighters.
Dan's two losses were on points against Selcuk Aydin in the winner's home country of Turkey.
"He is talking about the big fights (against Mayweather) then he is overlooking me," Dan, a southpaw, said of Brook. "I'm confident so it doesn't matter if he is overlooking me or not. I'm only concentrating on Kell Brook. I don't make plans for my next fight."