<P> The series follows Oliver Queen ( Stephen Amell ) , billionaire playboy of Starling City , who spends five years shipwrecked on a mysterious island . Upon his return to Starling City , he is reunited with his mother , Moira Queen ( Susanna Thompson ) and his sister , Thea Queen ( Willa Holland ) . In season two , following on from the devastating events of the Undertaking , including the death of his best friend Tommy Merlyn ( Colin Donnell ) , Oliver has vowed to stop crime without killing criminals , with the continuing aid of close allies John Diggle ( David Ramsey ) and Felicity Smoak ( Emily Bett Rickards ) . Oliver 's vow is tested when he comes under attack from Slade Wilson ( Manu Bennett ) , a man from Oliver 's time on the island who resurfaces with a vendetta against him . Oliver must also contend with outside forces attempting to take over Queen Consolidated , guilt from decisions he made in the past , and secrets harbored by his family and friends . Oliver grows to accept aspiring vigilante Roy Harper ( Colton Haynes ) as his protégé , and begins to receive assistance from Laurel 's father , Officer Quentin Lance ( Paul Blackthorne ) . Oliver also gains another ally ; a mysterious woman in black , who is eventually revealed to be Laurel 's sister , Sara Lance ( Caity Lotz ) , who had survived her ordeal at sea years prior . </P>
<P> The series follows Oliver Queen ( Stephen Amell ) , billionaire playboy of Starling City , who spends five years shipwrecked on a mysterious island . Upon his return to Starling City , he is reunited with his mother , Moira Queen ( Susanna Thompson ) and his sister , Thea Queen ( Willa Holland ) . In season two , following on from the devastating events of the Undertaking , including the death of his best friend Tommy Merlyn ( Colin Donnell ) , Oliver has vowed to stop crime without killing criminals , with the continuing aid of close allies John Diggle ( David Ramsey ) and Felicity Smoak ( Emily Bett Rickards ) . Oliver 's vow is tested when he comes under attack from Slade Wilson ( Manu Bennett ) , a man from Oliver 's time on the island who resurfaces with a vendetta against him . Oliver must also contend with outside forces attempting to take over Queen Consolidated , guilt from decisions he made in the past , and secrets harbored by his family and friends . Oliver grows to accept aspiring vigilante Roy Harper ( Colton Haynes ) as his protégé , and begins to receive assistance from Laurel 's father , Officer Quentin Lance ( Paul Blackthorne ) . Oliver also gains another ally ; a mysterious woman in black , who is eventually revealed to be Laurel 's sister , Sara Lance ( Caity Lotz ) , who had survived her ordeal at sea years prior . </P>
who played sara lance in arrow season 2
who played sara lance in arrow season 2
Caity Lotz
Caity Lotz