With pantomime and neon on overdrive, Katy Perry's Witness tour delivers live at London's O2

Katy Perry's very own curveball-lite Witness was not so much of a reinvention - more a badly judged refresh; light on sugary pop, big choruses and a sense of urgency. It felt like her weed record after two incredible amphetamine releases. Maddeningly, Taylor Swift's embarrassing Reputation - a terrible record - clocked up two million sales in its first week while Witness has barely topped a million to date.

Why then does it feel like Perry has nothing to prove tonight? She is - as always - unflappably reliable and confident in everything she does. Witness may have been a commercial flop but it did come with a few decent tracks (as well as a killer Minaj verse and some delicious Taylor-baiting lyrics).

If this was a Taylor show, expect Karlie Kloss or Ed Sheeran to make an appearance. But it's a trademark Katy Perry moment - a surrealist spectacle that that meshes Jeff Koons, Salvador Dali and Yuko Shimizu through a Homer Simpson dream sequence. We get walking cherry-flavoured chapsticks and an (almost excessive) cameo from the infamous and much loved Left Shark. At times it feels like a Yoshimi-era Flaming Lips show crossed with a live action remake of Gerald Scarfe's animations in "Another Brick In The Wall". And all the while, the all seeing eye on the backdrop plays Windows 95 screensavers and cold-war era stock footage.

There is no understatement - much of it doesn't make sense but does that really matter? It's all delivered with immaculate choreography, an Instagram-tuned narrative and a very knowing wink. There are giant pepper shakers, flamingos and lots and lots of f-cking cubes. And the songs? The tracks on Witness dominate more than they should (with the omission of "Hey Hey Hey" being a crime) but and the inevitable third act lull doesn't last too long before she deliver a splendid "Firework" before disappearing into a giant hand for the final jaw-drop.

Setlist

Witness
Roulette
Dark Horse
Chained to the Rhythm
Teenage Dream
Hot N Cold
Last Friday Night (T.G.I.F.)
California Gurls
I Kissed a Girl
Déjà Vu
Tsunami
E.T.
Bon Appétit
Wide Awake
Into Me You See
Power
Part of Me
Swish Swish
Roar

Encore
Pendulum
Firework