In the middle of the crowd, a gaggle of about 40 people is squatting down, beckoning others to do the same. Onstage, Kasabian are playing "Fire", the final song of their encore. Guitarist and birthday boy Serge Pizzorno – skinny of limb, big of hair and streaky of eyeliner – is striking an angled pose at his microphone. Singer Tom Meighan – quiff, claret drainpipes, shades – is egging the audience on.
Soon, by common consent, almost 20,000 people have crouched low, waiting for "the drop" – the bit where the bass comes in and the guitarists hit their effects pedals and the levee breaks. Boing! Up they all pop, clothing and beer arcing overhead. Someone is waving a crutch.
In the cold light of day, the act of watching an arena-ful of people sit down and then leap up again on musical cue like lubricated Pavlovian hounds might not seem all that significant. For all the latterday talk of their wisdom, we still see crowds as fundamentally dumb. But this act of mass theatre is not the sort of carry-on you would have seen at an Oasis gig, where people are more likely to deck one another than hit the deck for sport. And for that, this Leicester band – guardians of rock's fundamental ridiculousness – deserve some respect.
Although their success has been widely understood in the context of Oasis's demise, Kasabian prove tonight that they can be a slinkier proposition than mere lad-rock stand-ins. Despite four albums in which to find their true voice, a number of their songs do still plod along in other people's slipstreams, not least the Gallaghers'. But "Thick As Thieves" – one of those songs that is little more than an echo of a rewrite of an influence – ends tonight by quoting "People Are Strange" by the Doors. That's a bit of the 60s rarely acknowledged by Brit-rock, a genre basically run by mods. After a New Year's Eve gig back here at the O2, the next stop on Kasabian's travels is the US, where their latest album, Velociraptor! – which topped the UK chart with sales of 350,000 – didn't ruffle the Billboard 200. The Doors might come in handy there.
Although reports of Kasabian's experimental bent have been overstated, there is something intriguing about a band whose fairly workaday songs nonetheless sneak in a little frisson or two by the back door. The cleverest bits of tonight's set are to be found in the bridges and joins, or the psychedelic patches on tracks such as "ID" rather than the headline oomph-alongs such as recent single "Re-Wired".
You warm, too, to Pizzorno's butch effeminacy and his fondness for the dressing-up box. Tonight's gig starts off with the strongest track from Velociraptor!, "Days Are Forgotten", with Pizzorno flouncing about in a parka fringed with feathers. Of the seven men onstage, one is a trumpeter, who just adds subtle little parps. Ever since the Verve sampled a Rolling Stones string section at the start of "Bittersweet Symphony", British rock bands have felt compelled to hire string sections when they want to be taken seriously. Kasabian are no exception, touring with a quartet called the Dirty Pretty Strings, who add largely superfluous noises tonight.
Kasabian's best foot forward isn't shod in a Chelsea boot however. "Club Foot", the band's first single proper, is still redolent of Screamadelica-era Primal Scream, and remains Kasabian's surest pose. When bassist Chris Edwards and drummer Ian Matthews propose a groove tonight, or keyboard player Ben Kealey unleashes a housey piano line on a song such as "LSF", it's the scent of the Chemical Brothers that wafts along on the O2's thermals, rather than reheated meat and potatoes. Best of all is "Switchblade Smiles", which starts with an almighty electronic burble and doesn't flag. All of a sudden, their New Year's Eve gig in the company of neo-drum'n'bass duo Chase & Status doesn't look like such a tokenistic fit.
