Actor Simon Pegg attends the European Premiere of Ready Player One in London. Picture: Reuters.

Simon Pegg has opened up about his battle with alcoholism and doesn't think he'd still be alive if he hadn't been to rehab.

The 'Hot Fuzz' actor - who has nine-year-old daughter Matilda with wife Maureen McCann - was "owned" by his addiction and is thankful he sought help in 2010 and was able to explore why he had hit the bottle amid feeling depressed.

He said: "It was awful, terrible. It owned me...

"I got into it [in rehab]. I got into the reasons I was feeling that way. I went into AA for a while, too."

Asked how destructive his addiction had become, he admitted: "I don't think I would be here now if I hadn't had help."

Before he went to rehab, the birth of his daughter made the 48-year-old star realise he needed help.

He explained to The Guardian newspaper: "It was the most cosmic experience of my life.

"I thought it would fix things and it just didn't. Because it can't. Nothing can, other than a dedicated approach, whether that's therapy or medication, or whatever."

The 'Mission: Impossible - Fallout' star isn't "ashamed" of his problem but isn't "proud" of that period in his life because it was so "terrible".

He said: "I'm not ashamed of what happened. And I think if anyone finds any relationship to it, then it might motivate them to get well. But I am not proud of it either - I don't think it's cool, like I was Mr Rock'n'roll, blackout and all that s**t. It wasn't, it was just terrible."

Simon was able to successfully hide his problem for a long time, until the signs became too "obvious" to ignore.

He said: "I hid it...I'm an actor, so I acted ... all the f***ing time.

"One thing [addiction] does is make you clever at not giving anything away. People think junkies and alcoholics are slovenly, unmotivated people. 

"They're not - they are incredibly organised. They can nip out for a quick shot of whisky and you wouldn't know they have gone. It's as if ... you are micro-managed by it.

"But eventually the signs are too obvious. You have taken the dog for one too many walks."