Brian Wilson cuts a frail picture as he hobbles on stage.

20 years ago it would have been inconceivable to see him perform, but since then he has become a popular live act and experienced something of a latter day career renaissance. Much of this is down to The Wondermints, Wilson’s backing band who carry the show when their leader needs to take a step back.

He enters the stage with some gusto, and says “Hello Liverpool!” like he is genuinely happy to be here, and wastes no time in giving the audience exactly what they want. “We’re gonna open with an old Beach Boys song called California Girls!”

Opening with the first song he ever wrote on LSD somehow felt proper for a celebration of Pet Sounds. It also set a precedent for the first half of the show – a breeze through Beach Boys classics, fan favourites and deep cuts. For a band that could have easily been dismissed as a novelty act after a couple of years, you can’t help but marvel at how well much of the material stands up.

They frontload the show with I Get Around, Little Deuce Coupe, Surfer Girl and In My Room, before they delve deeper into the songbook. 1965’s Salt Lake City and a handful of songs from the Wild Honey album were unexpected but welcome additions.

What makes Brian’s band so special right now is the inclusion of Beach Boys co-founder Al Jardine. His presence means there are more founding Beach Boys on stage than there are in the actual Beach Boys these days.

Jardine takes the lead for much of the show, and introduces his son Matt, who takes the falsetto vocals that Brian can no longer sing, hitting unnatural notes whenever he opens his mouth. His lead on the glorious Phil Spector-inspired Don’t Worry Baby dropped jaws around the arena.

Towards the end of the set, former Beach Boy and sometime Rolling Stones sideman Blondie Chaplin joined the band for a trio of tunes. In truth, Chaplin’s style is a little at odds with the rest of the band. You can tell he has been hanging around with Keith Richards. He well and truly takes over the stage, prowling around particularly during Wild Honey.

Despite this, and his solo on Sail On Sailor being a little out of place, he is eternally charismatic and added a jolt to the evening.

After a short break, the second half of the show was a performance of Brian’s masterpiece – The Beach Boys’ Pet Sounds.

Much of Pet Sounds itself actually increases in poignancy with Wilson’s frail state. Brian singing a song like Don’t Talk (Put Your Head On My Shoulder) or I Just Wasn’t Made For These Times in 2017 is far from note perfect, but all those years of heartbreak, struggles and sadness suddenly come into focus and the brilliance and bravery of this man puts a tear in your eye.

He gives short, sharp introductions to many of the songs, but nothing that gives you any insight. “Here’s one with just music, no words. I think you’ll like it,” or “The drums on this one will blow your mind.”

At times, the scale of the performance feels more like a symphony. You could argue that this is as close to a classical piece of music as pop ever got.

The crowd comes alive at the album’s mid-way point. Al Jardine sings lead on Sloop John B, before introducing “The best song he ever wrote”, pointing at Brian who takes the lead on God Only Knows.

Jardine has a point. God Only Knows is about as perfect a song as you could produce. It feels right that Brian be given centre stage for it. He may struggle on the higher notes, but he doesn’t back away from them. The song receives a standing ovation, partially, it seems, just for existing. Wilson remains somewhat humble about it; “Oh, thank you! Thank you! Please, be seated!”

At the end of Caroline, No he darts off stage mid-song, the moment his part is done. It seemed odd, but underlines his shyness and lack of comfort in the spotlight.

But, of course, he returned. The encore was the songs that are on ever Jukebox in the world. Everybody was standing for Good Vibrations, Help Me Rhonda, Barbara Ann, Surfin’ USA, Fun Fun Fun. There was a full-on rock & roll dance party. People were pretending to surf on imaginary boards. I glanced to the right and saw a kid of about 7 or 8 years old with his grandparents. He was singing every lyric and playing air drums with a giant grin on his face, an enduring image if there ever was one.

He finished with the sole solo track of the night, and one of his most touching songs; Love and Mercy. It always feels like a message, a hymn to the world and distillation of his ethos; “Love and mercy to you and your friends tonight”.

At 75 years old, it is clear that Wilson is in his twilight years, and watching him struggle to walk on and off stage makes this especially apparent. It also often feels as if the show is happening around him, rather than him driving it.

But people love Brian Wilson so much that we are happy to simply be in his presence. His legend, genius and personal struggles have generated an affection for him that few performers receive. There is a warmth to him – when he loses himself in the music, it is truly transcendent. You almost want to give him a hug.

Mike Love’s “official” Beach Boys may be more technically proficient, but they lack the heart. And Brian’s heart is the most important thing.

Love and mercy, Brian.

Pictures by Brian Sayle