The former PM as you've never seen him: Sir John rocks gumboots and shorts, doing 'gangsta' handshakes

He's wearing iconic black gumboots and shorts greeting his DJ music producer son with a "gangsta" shake before a question-and-answer session with his son that promises to tell all.

From the expensively furnished lounge of "Club Parnell" former prime minister Sir John Key features as the special guest on the first instalment of Keyed In, a special segment tagged on the end of Max Key's lifestyle and music promotion vlog.

He needs three takes before the retired leader gets the carefully choreographed handshake down pat. In undoubtedly relaxed but mismatched attire, he takes his seat to answer the question the nation wants to hear - who will win the election?

And there's one rule - he must answer in 20 seconds from the time the questions starts.

Taking the role of interviewer the young Key launches into a long-winded lead-up reminding his newly knighted father of some of the more infamous gaffes of his leadership.

"So John, in your tenancy as Prime Minister there were ups and there were downs," begins Key.

"We're talking when you said "trotey" in front of the entire world - not your finest moment - there was the three-man handshake, there was the infamous hot dog we all know about."

Sir John grimaces as he is reminded about moments he would perhaps prefer were forgotten. They include creating the new word "trotey" during the opening ceremony of the 2011 Rugby World Cup and the awkward three-way handshake with Richie McCaw and International Rugby Board chairman Bernard Lapasset during the final Cup presentation.

"So why we are here today is we want to know with the 2017 election coming up, we're talking National, we're talking Labour, we want to know as former prime minister who you think is going to win the 2017 election," finished Max.

As Sir John launches into the answer he is cut short after two words as the stop clock winds down.

It's not the first time Sir John has featured on social media with his son. In 2011 Max Key posted a Facebook photo of himself planking in the family lounge with his father in the background.