KSI's brother Deji fell to the ground in shock when the Britain's Got Talent judge got epic revenge on him with a live prank on Lorraine.
Saturday's instalment of the ITV talent competition saw the YouTuber's younger brother take to the stage wearing a gold mask and black hood to conceal his identity.
After blindfolding KSI, 28-year-old Deji taunted him by revealing details about him that no one would know, before making him listen to his own music and unleashing his greatest fear - a box of bugs.
KSI, 31, was left screaming and begging the act not to bring them near him as he proceeded to tickle him - but the real shock came when he revealed his identity.
However the YouTuber and boxer managed to get revenge on his brother during Monday's episode of Lorraine, when Deji sat down with host Christine Lampard, 46, to discuss his playful trick live on air.
During the interview, Deji revealed: 'My main goal was to prank my brother. I didn't want him to know it was me, so I tried to change my manner, the way I was walking, I was trying to change things around really.'
KSI's brother Deji (pictured) fell to the ground in shock when the Britain's Got Talent judge got epic revenge on him with a live prank on Lorraine
The YouTuber and boxer managed to get revenge on his brother during Monday's episode of Lorraine, when Deji sat down with host Christine Lampard (pictured) to discuss his playful trick
Saturday's instalment of the ITV talent competition saw the YouTuber's younger brother take to the stage wearing a gold mask and black hood to conceal his identity
He also admitted that the two siblings had shared a disagreement just before his audition which spurred him on to trick his brother even more.
Christine quipped: 'He's going to try and set you up now isn't he? Is this what you worry about now?'
'I've been avoiding him, so yeah,' Deji laughed before a crew member dressed as a clown crept on set and shouted 'Boo!' in his face.
Deji screamed in shock, leapt to the floor and exclaimed, 'Oh my gosh!'
'I'm so sorry, you know I wouldn't do that to you, would you like to hear what he has to say?' Christine said as she laughed.
KSI then appeared on screen and shouted: 'Got ya bro! Thank you so much Christine for pranking Deji. Getting pranked on BGT, national TV, very embarrassing. It was funny, I'll admit it was very funny, but embarrassing. So I'm so glad we got you back there.'
'I've been avoiding him, so yeah,' Deji laughed before a crew member dressed as a clown crept on set and shouted 'Boo!' in his face
Deji (pictured, right) screamed in shock, leapt to the floor and exclaimed, 'Oh my gosh!'
Speaking to The Mirror after the audition, KSI said: ''I was blind to it all. 'When I got pulled up on stage, I just thought, 'Here we go. How is he going to torment me?'
'He gets me up on stage and he mentions a girl I was involved with years ago, no one really knows about her, only a specific few people do.'
He added: 'This guy is gonna just say things that no one should know. I was tripping balls! I couldn't believe it. And then he gets bugs out, that's a genuine fear of mine.'
Viewers rushed to X to react to the moment on Britain's Got Talent, writing: 'Deji pranking KSI on #BGT fully had me crying with laughter.'
'That was one of the best things I seen. Nice one. Sorry @KSI #BGT.'
'OMG I don't normally like Deji but what I just saw on BGT was really funny. I should have guessed it. #BGT #brilliant.'
'Shame Deji didn't stay on, seeing KSI be 'tormented' is worth watching this show alone tbh #TheTormentor #BGT #BritainsGotTalent.'
KSI was left screaming and begging the act not to bring them near him as he proceeded to tickle him - but the real shock came when he revealed his identity
Speaking after the audition, KSI said: ''I was blind to it all. 'When I got pulled up on stage, I just thought, 'Here we go. How is he going to torment me?'
'Stop it I was SOOO excited to see Deji on BGT with KSI! That was too good #BGT #BritainsGotTalent.'
'I have to admit that was really good, great prank,the best moment of the show this series,ksi brother pranking KSI, well done producer really good, thinking out of the box #BGT.'
'That was hilarious & brilliant Deji on BGT you love to see it. Sorry @KSI. That was great seeing the bros together #BGT #BritainsGotTalent.'
Lorraine airs weekdays at 9am on ITV1 and STV, and is available to stream on ITVX
