In the 1980s, one of Mark Thomas' early contemporaries - a certain Ben Elton - used to have audiences eating out of the palm of his hand with his aside, 'a little bit of politics'. Elton's ironic narrative was funny not least because it usually followed an especially savage comic rant against the Tory government of the day and 'Thatch' in particular.

Even in his early days, Mark Thomas' comedy was political, if at times - unlike Ben Elton - he seemed unhappy not just about 'Thatcher's Britain', but about absolutely everything. Whilst still being categorised as straightforward stand-up, Thomas should have thrown in his own aside - 'a little bit of comedy' - to remind audiences (and himself, one suspects) of the primary billing for his gigs.

The reality is that Mark Thomas was never really just about making audiences laugh. He had a serious point to prove and whilst this undoubtedly turned casual viewers and some of the paying public away from him, it also found him a new audience. More than 20 years on, Mark Thomas has found his place (in fact he did a while ago).

In 2010, he embarked on an audacious 'ramble' the entire length of the separation barrier between Israeli and Palestinian territories. Thomas' latest show - and book - recount this 750km walk under the title, Extreme Rambling.

His motivation is clear now and he's not just an angry man venting vitriol in the guise of stand-up. Mark Thomas is a serious, one imagines somewhat tortured, individual with a good heart who wants to highlight many of the failings and hypocrisies of the modern world. And his audiences love it, which is why two extra weeks of dates at the Tricycle Theatre, London, have been added after the first run sold out.

The extended run ends on Saturday 28th May, before a series of nationwide tour dates, currently ending in September in Aberystwyth. Tickets are on sale, prices typically start at £10-£15 (£17 for London).

Update: Edinburgh Fringe shows announced!

Mark will now also bring his show to the Edinburgh Festival Fringe, playing the Bongo Club nightly, from the 8th until 20th August. Tickets cost £14.50 - on sale now.