This is the Guardian. This summer see the European box office smash that critics aren't raving about

The count of Monte Cristo is timeless and thrillingly new. Five-star says total film.

Rotten tomatoes rates it at 100%. It's a big exciting swashbuckling

adventure stunning, a genuine triumph based on Alexander Dumas's classic tale.

A few count of his life. The Count of Monte Cristo, in Cinema's now, certificate 12A. They can send you on a journey through waterfalls of twisting colours, turn you into a floating

orb of light or make you feel like you're slowly sinking

into the floor.

But increasingly, the mind-altering powers of psychedelic drugs like LSD,

MDMA and silosibin aren't just being experienced at raves and in muddy fields.

In hospital clinics and research labs, they're being tested to see if they can treat a range of mental health disorders from depression to PTSD.

So far these are proved difficult to treat with conventional medicines and therapies.

Right now the evidence for psychedelic therapy looks promising, so much so that the market

is already worth billions of dollars.

But exactly how effective are these drugs?

What does scientists really know about how they work and the risks they pose?

And how long could it be before they reach a clinic near you?

I'm the Guardian Science Editor Ian Sample and this is Science Weekly.

Hana Devlin, you're a science correspondent at The Guardian and at the start of this year we did a look ahead episode together and one topic you mentioned that I thought we should dive a bit deeper into was the use of psychedelics to treat mental health problems and addiction issues.

Take me back a bit. Where did this research really start?

Psychodallics has got quite a long history in medicine.

Initial interest began more looking at how psychedelic drugs could help us understand the basis for psychiatric

disorders, so using them as trying to understand mental illness, and then over time this

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