The episode will also guest star Cynthia Addai-Robinson as Amanda Waller and Karl Yune as Maseo.
You can see the full synopsis below.
“The Return” — (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV)
THE RETURN OF DEATHSTROKE AND TOMMY MERLYN — Malcolm (John Barrowman) puts Oliver (Stephen Amell) and Thea (Willa Holland) in a dangerous situation that lands them on Lian Yu with Oliver’s former enemy, Deathstroke (guest star Manu Bennett). A flashback reveals when Oliver and Maseo (guest star Karl Yune) returned to Starling City to retrieve the Omega bio weapon, and despite being under strict orders from Amanda Waller (guest star Cynthia Addai-Robinson) not to reveal himself to anyone, Oliver looks in on his family, Laurel (Katie Cassidy) and Tommy (guest star Colin Donnell). Dermott Downs directed the episode written by Marc Guggenheim & Erik Oleson (#314). Original airdate 2/18/2015.