The Opium club in Barcelona caters very strongly to tourists and is one of the most visible nightclubs in Barcelona, with an open stone facade and a bold sign outside. You literally cannot miss it. Many people get interested in it after seeing it from the beach during the day.
The outside includes some outdoors seating which is especially good in the Summer, but a bit too cold in the Winter. It is on an elevated deck, so you can look out over the beach front without worrying much about sand or passers-by. It still retains an air of intimacy even though you are out under the stars. The outdoors seats are very comfortable, with large white couches and stools, and plenty of cushions. If the weather is warm you will love it out here.
Indoors the lighting is beautiful, with ornate glowing LED patterns in the ceiling and some night spotlights. It might be a bit bright for some people, but it is generally quite a pleasant lighting and still very flattering for selfies and dancing. The seating indoors may seem a bit random, with curved couches wrapping into each other a bit like a Paisley print, but it's actually very well designed for people who want to mingle and have fun with the other club-goers.
The stage is very visible from everywhere in the club and you will be able to enjoy the music and show wherever you are seated nor dancing. They play very loud, international music, with a bit of an American leaning. This Barcelona nightclub has a bit of a Las Vegas feel to it.
The drinks are pretty standard for a Barcelona club, but pretty good nonetheless. The price for drinks and hookah runs quite high, and you are paying more for the experience and the venue than for the drinks themselves, which aren't amazing, even if they are good.
It can get insanely crowded with a very international community as the night goes on. As it attracts mostly tourists you will find it easy to talk to people in English. Thanks to how many people are drawn to it during the day, it tends to be buzzing with life as the night goes on. It also opens late, as most Barcelona nightclubs do, with the biggest energy building in the early hours of the morning. And it stays open literally all night long, so if you have the energy you can have a great night out clubbing and just wait for early in the morning to have a coffee and set off around the city again.
The venue is in very high demand and you may not be able to get in much after one or two in the morning. It is recommended to sign up on the guest list so that you can get in early and sometimes receive free entry. Otherwise there is a pretty standard door fee for men, and a fee sometimes waived for women.