Olly Alexander has delivered his first Eurovision Song Contest performance, which featured upside-down locker room staging.

Cameras were rotated to give a spinning feel to Alexander and the dancers as the singer wore a white singlet, red trousers, and boots which looked a little distressed at the Malmo Arena in Sweden.

The rendition of Dizzy was energetic, and it is the first time the UK, which is already through to the finals, has performed in a semi-final.

Sweden Eurovision Song Contest Semi-Final
Bambie Thug of Ireland performs the song Doomsday Blue (Martin Meissner/AP)

Earlier, Bambie Thug brought an intensive and dramatic performance which saw them triumph with the crowds by doing a witchy and mesmerising execution of their chanty alternative song Doomsday Blue.

Their male dancers also looked almost devil-like with blue paint, highly exaggerated ears and fake teeth.

Halfway through the end of the song, Bambie – who uses the pronouns they/them – also revealed the trans flag on their costume ahead of fire being set around the stage.

Lithuania’s Silvester Belt also went down a storm when he carried out a highly synchronised and mind-bending rendition of his song Luktelk.

For much of the staging, he was clad in red and black lights as dancers did almost robotic moves beside him.

Also in the top half of the opening performances were Cyprus entrant Silia Kapsis with Liar and Serbia contestant Teya Dora with Ramonda.

For Ukraine duo Alyona Alyona and Jerry Heil, their religious infused Teresa & Maria brought huge attention from Malmo Arena as the impassioned singers complemented each other by singing and rapping.

Also drawing interest was Windows95man, who appeared to use clever camera angles to seem nude while on stage, as he emerged from a giant egg-shaped denim prop to perform No Rules!

Sweden’s entry Marcus & Martinus sang a duet of their song Unforgettable in a tight space, which looked like a dance party.

The Norwegian twins then emerged in front of the crowd as screens, which appeared to have computer code on them, and thanked the audience for the positive reaction when they were finished.

Elsewhere, Australia singer Zaachariaha Fielding from the group Electric Fields paid tribute to her Aboriginal heritage with a dancer wearing a traditional costume.

Eurovision was hosted by Swedish comedian Petra Mede and Hollywood actress Malin Akerman.