Sam Smith honours the late Brianna Ghey on Gloria tour

Trigger warning: this article contains sensitive content

Sam Smith put on a breathtaking performance as he graced the stage at The O2 in London this week.

The string of concerts kicked off his headline tour to celebrate his fourth studio album Gloria.

It was not solely Sam's impressive vocals and numerous outfit changes that floored us, but his touching tribute to the late Brianna Ghey, which tugged on our heart strings the most.

Prior to singing a cover of Des'ree's Kissing You, Sam changed into a vibrant green billowy gown with uber puff sleeves, and adorned a halo headband, which also resembled a crown. 

On closer inspection the headpiece had "Brianna Ghey" emblazoned on.

This was a subtle honour from the 30-year-old powerhouse, as he did not mention Brianna prior to the outfit change, and proceeded with the heartfelt ballad.

The transgender teenager was tragically killed in February in what the police suspected to be a possible hate crime.

The 16-year-old was stabbed to death in Linear Park, Cheshire, and now two teenagers have reportedly been arrested and charged with Brianna's murder, with Cheshire Police confirming that a 15-year-old girl from Warrington and a 15-year-old boy from Leigh were in custody.

The trial begins on July 10, Billboard has reported. 

Candle-lit vigils were held across the UK at the time in Brianna Ghey's memory, and Brianna, and her grieving family, still remain in our hearts and thoughts months on. 

Elsewhere, the Too Good At Goodbyes hitmaker reassured audiences his concert was a "safe space to let your freak fly", as he encouraged crowds to follow their dreams. 

He said: "This room and this venue is very special to me. And very special to so many of us because so many of us come from London. 

"Whenever I’m in this room, I will always remember being sat right at the back when I was seven and I went to see Rihanna and I had an umbrella. 

"So I have to shout out to the kids right now and say you can do this, you can do this. 

"This show is about many things, but the main thing for me is freedom. 

"I really want you guys to turn around to the person next to you because this is a safe space to let your freak fly. 

"Two years ago when I was at home dreaming about being on stage again, the thing I missed the most about being on stage was sharing my life and travelling around the world with the incredible artists and musicians I get to be with. I wanted to make sure when I came back I heard my favourite singers sing."