If you take the sexuality and general aesthetic of “The Rocky Horror Show” and cross it with indie rock and synth pop, you’ll end up with Thursday night’s of Montreal concert at The Ready Room.

The night started off strange as opening band Reptaliens took the stage. A ghillie-suit-clad man delivered a chilling promise of aliens among us before taking off the head of his costume to reveal an alien mask. The alien (also known as Bongo Guy or Austin) reappeared in nearly every song in their set, wearing a different costume each time. He played tambourine dressed as an Albert-Einstein-esque extraterrestrial mad scientist, played maracas in a tinfoil cape and hit bongos in a three-piece suit with a crocodile head. Some times (in an alien-Pope costume), he just danced; other times (in the ghillie suit again), he stripped.

The rest of the band wasn’t any less strange. Bambi Browning, Reptaliens’ lead singer, wore as much glitter as possible as she danced around the stage. She donned glittery boots, a sparkly sweater and leggings with sequined designs on them, the most notable of which was a devilish red cat rising from between her legs.

“This song is about getting abducted by aliens and falling in love with them, and wanting to…do things with them,” she said before their third song. This sentiment could easily be applied to every song in Reptaliens’ set. The lyrics were hard to make out at some points, but the music consistently felt atmospheric and strangely sci-fi.

Everyone on stage always had a huge, genuine smile on their face. The members of Reptaliens were having the time of their lives performing. So did the crowd, which started off virtually nonexistent but filled the room before the end of the set.

Things only got stranger when of Montreal took the stage. A man in a skeleton onesie and red ski mask confused everyone by running out onstage and providing an introduction for Kevin Barnes, the lead singer when the rest of the band was already playing.

When Barnes danced onto the stage, he did so with style. Sporting a curly blond wig, a black and white polka dot dress, red tights and sparkly red heels, Barnes threw himself into the first song of the set. The energy never died down—not between songs, not when Barnes ran offstage to change his outfit (he went through four more during the set, not including when he stripped onstage and performed two songs in just the tights, heels and a green wig), and not even after the band had left the stage. The crowd cheered louder than the music had ever been, it seemed, until of Montreal returned to give their encore.

During the show, Barnes’s numerous outfits were about the least strange thing happening onstage. The three backup dancers seemed determined to best the alien of the previous set through more extravagant and openly erotic performances. Though sometimes they merely dressed as robots or wore giant puppets or orange fur suits, more often than not they would enter wearing something more like this: one wearing a large horned headdress and holding a whip and two chains, which wrapped around the necks of the two others…or maybe it was the person wearing a magical girl costume, complete with a huge-eyed mask, or what was clearly supposed to be an alien orgy.

Through it all, the crowd danced and sang at the top of their lungs. The craziness had infected everyone, and they had the time of their lives. Next time of Montreal comes to town, go see them live. It will be a show you’ll never forget.