Kev and Nixxi celebrate reaching Show 100 with a proper studio party and an extended edition. Simon Gunton and Rob Davies join the celebrations, recurring features and jokes are revisited, and listeners who have followed the programme help mark the milestone through messages and interaction during the night.

The regular SmeggHeads questions tied, so the pair went to a tie-break about the number of dimples on a regulation golf ball. Nixxi won the decider.

With Show 100 only a week away, Kev and Nixxi started preparing for the big one while still finding time for the usual distractions. Kev unveiled the remarkably advanced technique of using a piece of paper to predict temperatures and also had a new bike, giving Nixxi and the listeners plenty to work with before the centenary celebrations.

Nixxi won SmeggHeads again, leaving Kev to be told that he had lost for another week.

Kev and Nixxi prepared for the end of the world after a much-publicised rapture prediction claimed judgement day was due to arrive at roughly the same time as the show finished. The pair treated the possibility with exactly the seriousness it deserved, planning around the apocalypse while listeners joined in and the normal Saturday-night programme carried on regardless.

Nixxi won SmeggHeads, proudly taking the result 'all by myself'.

A failed attempt by Nixxi to honk Kev's horn produced exactly the level of innuendo the title promised. Kev and Nixxi stretched the joke far beyond the point any sensible programme would have stopped, with listener messages helping to keep the horn-related nonsense alive between the music and regular features.

Kev won SmeggHeads 4-3 after a close round.

Nixxi attempted to educate Kev on the history of Ireland, which was always going to be a risky way to spend part of a Saturday night. Kev's lack of hair somehow became evidence that he could not sing, and the history lesson steadily gave way to the usual Kev and Nixxi logic as listeners joined the conversation.

Kev had a strong SmeggHeads and won the week after getting five answers right.

Nixxi arrived with a new green-bean diet, giving Kev exactly the sort of material he could be trusted not to leave alone. The competitive part of the night went even worse for her when Kev demolished her in SmeggHeads, with the quiz becoming another excuse for the pair to gloat, argue and drag the listeners into the fallout.

SmeggHeads went emphatically Kev's way, with the original episode notes summing it up as Kev having 'pwned' Nixxi.

Barbecues, ducks and surprisingly serious opinions about fencing sent the conversation in several directions, before Alex Humberstone added a rap to the night's collection of nonsense. Kev and Nixxi bounced between the listener messages, the music and each new distraction as one subject repeatedly crashed into the next.

Alex returned as quizmaster and Kev took the SmeggHeads win.

The early-millennium specials reached 2003, and Kev and Nixxi quickly discovered that remembering a year fondly and actually finding two hours of brilliant records from it were not necessarily the same thing. They worked through the hits, judged what still sounded good and happily tore into the ones that did not, with the usual listener reaction joining the argument.

Simon ran SmeggHeads. The regular round finished 4-4 before a tie-break about Simon's birth year, and Nixxi won the decider.

The 2002 special opened with Nixxi back in the studio, hyper on marshmallows and turning the box from an early Easter egg into an Art Attack-style photo frame for Graeme Fenwick. Kev and Nixxi then raided 2002 for the night's music, digging through Four Strings, DJ Shog, Dee Dee, Humpenberg, Matt Darey, DJ Alligator and plenty of records they were rather less convinced deserved another airing. Earth Hour arrived mid-show, so the studio lights went out and Kev and Nixxi attempted to carry on in near darkness using their computer screens and an iPhone as illumination. Inevitably Kev struggled to see the buttons, Nixxi accused him of secretly putting a light back on because he was scared of the dark, and saving the planet briefly became considerably less important than actually keeping the show on air. Listeners joined the 2002 nostalgia through Interact and requests, with Shawn listening from America and reacting to some of the stranger records. A debate about ridiculously fast rappers ended with Kev attempting Busta Rhymes at speed, while Simon phoned in and was dragged into the usual abuse about Nixxi's eating habits. Later, Kev and Nixxi let the listeners into something normally done before the show: auditioning a promotional CD that had arrived in the post. They sampled tracks from singer and pianist David and asked the audience whether any of it deserved a place on the playlist. The night also included the usual Kev-versus-Nixxi quiz before the pair returned to squeezing as much good, bad and gloriously dated 2002 music as possible into the rest of the show.

The five regular SmeggHeads questions ended level, so Alex asked where he had gone on holiday in 2002 and gave the hint 'L'. Nixxi answered Lanzarote and won the tie-break, leaving the running score at Nixxi 14, Kev 10.

Kev announced that he had had a baby, giving Nixxi and the listeners plenty to talk about before the music headed back to 2001. The year special packed the show with the pop and dance records Kev and Nixxi remembered from the year, mixing genuine favourites with the tracks they were rather less delighted to hear again.

The 2001 special included a one-sided SmeggHeads: Kev won 4-1.