His experience in overcoming depression and making changes in his life led to a fascination with the practice.
A few years down the track, the former accountant and financial planner has a successful career as a stage hypnotist and could not be happier.
"I have to laugh when people say they are scared of hypnosis because they're worried they will lose control of their mind" Donnelly said.
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READ NOW"Nothing could be further from the truth.
"Hypnosis is not voodoo, magic or mind control; it is a natural state that we all experience every day."
Donnelly brings his comedy hypnosis show to the Brighton Hotel on Monday, with the emphasis on fun.
Audiences can expect to become involved in the show, but not be embarrassed.
"This is not the type of show where you will end up clucking like a chicken or barking like a dog," Donnelly said.
"That's a clich" from the old days, although some audience members still ask for it.
What you will see is people having a lot of fun on stage for the entertainment of the audience.
It is a show where the audience can become stars in a safe, tasteful and unforgettable way that will have you laughing and talking about the experience long after the show.
The former New South Wales Central Coast resident and father of three said his aim was to provide an entertaining and encouraging look at harnessing the power of the mind for good; as well as for comedy.
Donnelly is a master hypnotist, NLP Master Practitioner and a member of the Australian Hypnotherapists Association.
The first five people to call 0416 929 636 will each receive a double pass to the show.