Seven-time world champion Hendry retired from the sport five years ago but has been tempted to return this week at The Baths Hall, Scunthorpe.
The 48-year-old Scotsman - arguably the greatest snooker player of all time - is top seed and favourite to win the £10,000 prize and an invitation to compete at the World Championships in Sheffield next month.
But Lines, the 47-year-old who now competes as an amateur after several decades playing on the professional Tour, is determined to spoil the party when the tournament cues off tomorrow.
He clinched one of only four amateur spots – via qualifying tournaments in England, Ireland and Germany – to join the likes of Hendry, plus other Crucible champions in Bradford’s Joe Johnson, Dennis Taylor, John Parrott and Cliff Thorburn in Scunthorpe.
And while Lines admits the prize cash is a bonus, the Leeds potter is excited about competing against some of the sport’s legends.
“Obviously the money is good, but realistically for me, money has never been the reason I play snooker,” said Lines.
“It’s nice to have cash, but I have never had fortunes and I am probably never going to have fortunes.
“I just love snooker. Listen, I am not kidding myself that if I win I will be the world champion. I know it is what it is, there’s only 12 players and it’s an invitation event, but I would really, really just love to win it.
“That is the reason why I desperately wanted to play.”
Lines - who works full-time at the Northern Snooker Centre in Leeds - opens up against former UK champion Patsy Fagan, the 66-year-old Irishman. Victory would see him face 1985 world champion Taylor in the quarter-finals in a best-of-five frames contest.
Lines and Hendry are due to meet in Friday’s semi-final, if both reach the last four.
The other three amateur qualifiers include fellow Leeds player Jonathan Bagley, 46, Northern Ireland’s Patrick Wallace, 47, and Lowestoft’s Aiden Owens.
“People like Steve Davis and Jimmy White have won it before, so it would be amazing to join them as winners,” added Lines, who arrived back from playing in the European Championship in Cyprus yesterday.
“In an ideal scenario - in my mind - I wanted to get to the final and play Hendry there. But we have been drawn in the same half of the draw.
“Everyone knows how good Hendry is, and I think a lot of people think he will win it. But it will be tough, the four qualifiers are all good players.”
Despite now competing as an amateur, Lines has picked up some impressive results this season, including a 6-3 win over former world champion Neil Robertson at this year’s UK Championship in York.
He added: “I am really enjoying playing this season. The Northern Snooker Centre have been really supportive with having time off, with all the travelling I have been doing, and I couldn’t do it without their help.”
Hendry only arrived back from a business trip to China yesterday himself - he travels there every month - but is hoping he can put on a good show in Scunthorpe.
“The World Seniors has to be something a bit different, so there will be the likes of myself, John Parrott, Dennis Taylor, Joe Johnson - players when snooker was in its boom, from the Eighties and the Nineties,” said Hendry.
“These were the players that everyone watched, so this is a chance to see these guys play again.
“I land back from China on the 20th, after being there for five days, so I will need to get my cue out as soon as I can and get some work done. I am still working in China, I am there 10 to 12 times a year, I do my pundit work for the BBC and ITV, so that takes up a bit of time.
“I still do a few exhibitions, and have started playing a bit of poker, so I am trying to keep busy.”
If Lines does clinch a World Championship qualifying spot, he will be one of seven players competing who are sponsored by Litetask - the Leeds lighting company, who will donate £50 to St Gemma’s hospice for every century made in Sheffield.
Along with Lines, and son Oliver, Litetask also sponsor former world champion Shaun Murphy, David Gilbert, Ben Woollaston, Daniel Womersley and Joe Swail.
“St Gemma’s is Litetask’s chosen charity and a charity very close to myself after recently losing my father-in-law to cancer there,” said Mark Pears, Litetask’s managing director.