Where to start with a review of Derren Brown: Underground without giving the game away?

The master of mind control, showmanship and illusion takes to The Marlowe Theatre stage this week with a collection of his best material from the past 15 years.

It is an impressive and award-winning body of work that has seen him stick viewers to their sofas through their television sets and even convince a man to attempt to assassinate Stephen Fry.

So expectations were high as 1,200 packed into the Canterbury venue for Tuesday's opening night.

The show's theme is secrets, which Derren implores the audience - and any potential reviewers - to keep tightly under wraps.

Despite this, he claims to be somewhat of an open book, telling the crowd: "I am often dishonest in my techniques, but I am always honest about my dishonesty."

This is true to an extent. He lets us in on some tricks of the trade, such as describing the signals we unknowingly display that enable him to "read our minds".

I went to see a show of his in the mid-noughties, in which he held a seance on stage. He then revealed the tactics used by so-called mediums and mystics to manipulate participants into believing what they want to.

Nowadays, he largely keeps these techniques himself, clearly revelling in the awe-struck reaction from the audience. Many audibly gasped throughout the show. At several points, you do feel truly stumped as to how he pulls off such seemingly impossible feats.

Maybe he uses stooges? But he throws frisbees out into the auditorium to randomly choose participants. Perhaps an earpiece? But he goes to great lengths to show this is not the case. Maybe he has prior intel on audience members? It would require an enormous amount of research.

Always at least a few steps ahead, Derren is extremely clever, very quick-witted and clearly has a brilliant mind and freakishly good memory. Or maybe he really is magic. Whatever the case, the secret to his success is one he's certainly keeping close to his chest.

Derren Brown: Underground is at the Marlowe Theatre until Saturday. Tickets, costing £41.25 to £49.75, are available at marlowetheatre.com.