<P> In episode 19 she finds out that Jason is her brother . This information causes a divide in her family . During episode 20 Spencer and Wren rekindle their relationship, however Spencer was drinking during the event . It is Spencer that keeps digging into the "A" information, and is the one who eventually finds "A's" lair in the season 2 finale along with discovering A's identity...who turns out to be Mona . She is essentially kidnapped by "A," and during a scuffle accidentally pushes "A" off of a cliff, almost killing them . The rest of the girl's arrive shaken by the ordeal and finding out their tormentor's real identity . As the police arrive, Spencer is reunited with Toby, who says pretending not to love her back was the most difficult thing he's ever done . The two then make up passionately kissing as Spencer smiles happily while kissing him . </P> <P> Summer has passed since the unveiling of "A", and the girls think they are safe - little do they know they need each other more than ever . The first half of the season focuses on Spencer finding out who the black swan was: her sister . Melissa tells her she received the dress at her door - with a note threatening her to wear it - and she assumed that it was Mona . Spencer decides to believe her, but is still a little suspicious . She grows closer to Toby, even having sex for the first time in the episode "The Lady Killer". In the same episode, however, it is revealed (not to the liars, but to the audience) that Toby is a member of The A-Team . Hanna finds the key to A's new lair and gives it to Spencer . Toby sneaks into her house to retrieve it, not realizing Spencer set it as a trap to confirm her suspicions . She slaps him, after seeing him in the signature' A jacket' . She doesn't tell her friends, rather keeping it to herself . </P> <P> She gives the key to a private investigator and gives him a picture of Toby and her, before ripping it in half . She tells him in order to find where the key leads to, follow him . He leaves and Spencer disturbingly begins to rip her own half of the picture of herself . She begins to withdraw herself from her friends, and becomes emotionally unstable . She is angry, and starts to unravel and do things she knows she shouldn't (attacking Mona physically, and telling Jason that Alison was pregnant before she died with Darren Wilden, but had no physical proof). In the episode "Hot Water" she tells the girls the truth about Toby . Also in the same episode, she catches a glimpse of the girl in the red coat who is the leader of The' A' Team, but fails to catch up with her . In the episode "Out of Sight, Out of Mind" she finds Toby's dead body and tells him, "I love you". After failing to track Mona down in the woods she is found by a hiker in the morning with small injuries to her face and arms and is admitted to the Radley hospital in a catatonic state . She is unknown by doctors at the time and is simply known as,' Jane Doe' . When her identity is revealed to the Radley staff, Mona visits her . They have a long discussion and it is revealed in "I'm Your Puppet" that Mona somehow convinces her to join the A team . Spencer is the third known member of the A team . </P> <P> In the Season 3 finale "A Dangerous GAme", it is revealed that Toby is alive . She meets him at a diner, and he reveals he only joined The' A' Team in order to protect her . They get back together and have sex for the second time in a motel . Spencer hosts a fake party at a lodge where the girls are supposed to meet "Red Coat", when an unknown figure starts a fire, trapping Aria, Hanna, Emily, and Mona in the burning house . Toby leads Spencer in the woods to see who "Red Coat" is . Red Coat lands in a helicopter, and Spencer catches a glimpse of her face and says "Ali?". The girl in the red coat drags everyone out of the house, and Hanna wakes up, face - to - face with Alison . Although 3 of the girls (Spencer, Hannah, Mona) claim to have seen Ali, it is still not 100% sure that it was her, because it is possible it could have been a hallucination due to the effects of the fire . They drive and see Wilden's car dug up from the lake . They (including Mona) get a text: You're Mine Now . Kisses! - A, which is written in red font . They open the trunk, gasping and horrified at what they see . </P>

When does spencer become part of the a team