He lurches towards me across the space between the kitchen bench and the dining table. Armed with two cups of tea, he makes an alarming sight but, against all the odds, he makes it without spilling a drop.
"I wouldn't have been able to do that three months ago," he says, with an involuntary shudder. "I would have thrown it all over the floor."
His name is Andy McDowell and I'm proud to say that he's a mate of mine, though I'd lost touch with him when I saw him at the Mt Albert Aquatic Centre in the autumn.
He was swimming widths under the close supervision of an instructor and I thought, 'Well, who would have thought old Andy didn't know how to swim?' But all was revealed when we met up later.
Out of the water that had covered most of him, he was unrecognisable. His torso muscles were pitifully wasted and he jerked as he talked, throwing his chin forward in what looked like an act of aggression by a drunk. ("Yeah, I get that a bit," he says. "People think I'm drunk, and that's okay.")
What those people don't know is that Andy was diagnosed, in December 2009 at 43, with Parkinson's disease, a degenerative disorder of the central nervous system resulting from the death of cells in the mid-brain that produce a neurotransmitter called dopamine.
Until July, he managed the symptoms with heavy medications - cruelly, the random and involuntary movement known as dyskinesia, is a side effect of the medication, not a primary symptom of his disease. But in July, he underwent a surgical procedure to implant electrodes in his brain.
A few weeks later, a battery pack was installed under the skin of his upper chest, near his collarbone and the so-called deep-brain stimulation went live. The effect was ... electric. His medication has been cut back, and the dyskinesia has reduced massively.
"I got my groove back," he says. "And I got my smile back too."
He's not just talking about a change of mood. A less obvious symptom of Parkinson's is what is known as facial masking.
When Andy smiled, the right side of his face didn't, so he looked permanently grumpy. And Andy has always been quick to smile and to make others smile, too. "Welcome back, smile," he wrote in a blog post. "I missed you."
Writing - a strength for a man who has his own marketing company - has been a major lifeline for Andy over the past five years. Six months after he was diagnosed, he wrote a poem entitled Smaller, which he calls "a small poem with a big idea".
"My world got smaller," the first few lines run, "my handwriting / my voice / my walk / my spirit / my balance / the space in the world I take up."
Two years later, he was introduced to children's book illustrator Ross Kinnaird, and the poem got some pictures; then designer David Craggs and his colleagues at Franklin Road Studios made the pictures move. And last year, on an impulse, Andy submitted the result to a video competition run by the World Parkinson's Congress being held in Montreal.
The challenge was a global competition in which people with Parkinson's or in the Parkinson's community - family or caregivers - had three minutes to tell a story. In Andy's entry, his daughter Lily recites the poem and it's pretty hard to watch without tearing up, even though - or perhaps because - it ends on an upbeat note.
What happened next seemed inevitable. "Holy Toledo! We won!" runs his blog post for October 1.
His writing is motivated in large part by his need to explain to his kids, Lily, 8, and Pearl, 5, what's going on. He calls his disease "Parky" and the facial masking comes when Parky brings "his mate Mr Grumpy to visit".
"I'm always conscious that it's uncomfortable for people being around me," he says, "and if I can make a joke about it, particularly around children, it makes it easier."
Andy tells me that he has mostly managed to resist self-pity and anger.
"I have felt anger at times, but it's pretty futile. I think it was Bruce Lee who said, 'Do not pray for an easy life; pray for the strength to endure a difficult one'.
"I had a pretty easy coming into the world so it's quite nice finding my inner core and my toughness now."
For more information and to watch the video go to Andy's site: www.smaller.co.nz
Parkinson's Awareness Week begins on Saturday.