Versteeg, a member of the Blackhawks 2010 Stanley Cup championship team, has two-years left on his contract beyond this season, at an annual salary of $4.4 million.
"We are excited to bring Kris back to Chicago and are pleased to add a player with his experience and versatility to our lineup," said Blackhawks VP and GM Stan Bowman. "Kris is well respected within our organization and will be able to make a seamless transition to our team because of his familiarity with many of our players and with Coach Quenneville. This move strengthens our team depth and Kris' skill is a great complement to our current roster."
Versteeg, 27, has registered two goals and five assists for seven points in 18 games this season with the Panthers.
The Lethbridge, Alberta, native has accumulated 92 goals and 120 assists for 212 points in 349 career NHL games with Chicago (2007-10), Toronto (2010-11), Philadelphia (2011) and Florida (2011-13).
He was originally selected by the Boston Bruins in the fifth round, 134th overall, of the 2004 NHL Entry Draft before being acquired in a trade by the Blackhawks on February 3, 2007.
Lefebrve, 22, has recorded six points (2G, 4A) in eight games this season with the ECHLís Cincinnati Cyclones.
"We are pleased to welcome both Jimmy and Dylan to the Panthers," said Panthers GM Dale Tallon. "Jimmy is a young, strong, hardworking, versatile forward who brings both size and skill to our team. Dylan, a former first round draft pick, is a young, solid defenseman who adds further depth to our blue line. We thank Kris for his contributions to the Panthers, including helping us win 2011-2012 Southeast Division Championship, and wish him the best of luck in his return to Chicago."
Hayes, 23, has played in 43 career NHL games, all with Chicago (2011-14) scoring six goals with seven assists and 16 penalty minutes.
The Dorchester, Massachusetts, native was drafted by the Toronto Maple Leafs in the second round (60th overall) in the 2008 NHL Entry Draft.
Olsen, 22 has played in 28 career NHL games, all with Chicago (2011-12), registering one assist and six penalty minutes.
He was drafted by the Chicago Blackhawks in the first round (28th overall) in the 2009 NHL Entry Draft.