<P> Mona Vanderwaal ( Janel Parrish ) ( season 1 -- 7 ) is a former unpopular girl at Rosewood who longed to be accepted into Alison 's group and was continuously mocked by Alison . After Alison 's disappearance , Mona befriended Hanna and they underwent an `` extreme makeover '' together ; as a result , they both became popular students . When `` A '' appears , Mona becomes jealous of Hanna rekindling her friendships with the other Liars . She dislikes Caleb and makes attempts to break Hanna and Caleb up , though to no avail . She becomes romantically involved with Noel , much to Hanna 's disapproval , but is later dumped by him for Jenna . When `` A '' begins sending Mona threatening notes , she grows closer to the Liars . In the second - season finale , she is in fact revealed to actually be `` A '' when she and Spencer travel to the Lost Woods Resort to uncover `` A '' 's lair . She is committed to a mental institution , Radley , after being diagnosed with borderline personality disorder . Here , someone known as Big A takes the `` A '' game away from Mona and starts an `` A-Team '' , consisting of Mona , Toby , Spencer , Melissa , Wilden , and Lucas . At Radley , Mona gives answers to Hanna concerning Maya 's death . Possibly unbeknownst to Big `` A '' , she secretly gives Maya 's website to Hanna in code , leading them to eventually discover that Nate killed Maya . Mona reveals that a person in a red coat came along and changed the game , becoming the new `` A '' . Mona later reveals she actually does n't know who `` Red Coat '' is , and is basically expelled off the team for letting Spencer and Toby trick her . At the end of season three , Mona gets a text along with the rest of the girls in red font : You 're mine now . Kisses ! - A , implying she is now a victim of `` A '' . Mona begins helping Ezra with his book in 4B due to him blackmailing her because of her illegal `` A '' activities . In the season 4 finale , Alison reveals that Mona helped her the night she was hit over the head and convinced her to go into hiding . In Season 5 , she starts an army of Alison haters to prepare for Ali 's return . The team consists of Lucas , Melissa , Jenna , Sydney , and various other people that were treated badly by Alison . In the season five mid season finale , she is killed by Big `` A '' after acquiring information that proves Alison is Big `` A '' . In the second half of the season , it is revealed that Mona never thought Alison was Big `` A '' and instead , it was a plot by her and Big `` A '' to get Alison into jail . Mona was to fake her death as part of this plan , so that she could find out Big `` A 's '' identity , and in the fifth - season finale it was revealed that Mona is really alive and being forced to `` be '' Alison inside Big `` A '' 's Dollhouse . She escapes the Dollhouse with the other girls in season six , and ends up finding out Big `` A 's '' true identity to be CeCe Drake , alongside the others . During this revelation , Mona realizes that she was the one who hit Bethany Young with a shovel that night , believing she hit Alison , but discovering the truth once CeCe reveals that it was her who hit Alison . </P>
<P> Mona Vanderwaal ( Janel Parrish ) ( season 1 -- 7 ) is a former unpopular girl at Rosewood who longed to be accepted into Alison 's group and was continuously mocked by Alison . After Alison 's disappearance , Mona befriended Hanna and they underwent an `` extreme makeover '' together ; as a result , they both became popular students . When `` A '' appears , Mona becomes jealous of Hanna rekindling her friendships with the other Liars . She dislikes Caleb and makes attempts to break Hanna and Caleb up , though to no avail . She becomes romantically involved with Noel , much to Hanna 's disapproval , but is later dumped by him for Jenna . When `` A '' begins sending Mona threatening notes , she grows closer to the Liars . In the second - season finale , she is in fact revealed to actually be `` A '' when she and Spencer travel to the Lost Woods Resort to uncover `` A '' 's lair . She is committed to a mental institution , Radley , after being diagnosed with borderline personality disorder . Here , someone known as Big A takes the `` A '' game away from Mona and starts an `` A-Team '' , consisting of Mona , Toby , Spencer , Melissa , Wilden , and Lucas . At Radley , Mona gives answers to Hanna concerning Maya 's death . Possibly unbeknownst to Big `` A '' , she secretly gives Maya 's website to Hanna in code , leading them to eventually discover that Nate killed Maya . Mona reveals that a person in a red coat came along and changed the game , becoming the new `` A '' . Mona later reveals she actually does n't know who `` Red Coat '' is , and is basically expelled off the team for letting Spencer and Toby trick her . At the end of season three , Mona gets a text along with the rest of the girls in red font : You 're mine now . Kisses ! - A , implying she is now a victim of `` A '' . Mona begins helping Ezra with his book in 4B due to him blackmailing her because of her illegal `` A '' activities . In the season 4 finale , Alison reveals that Mona helped her the night she was hit over the head and convinced her to go into hiding . In Season 5 , she starts an army of Alison haters to prepare for Ali 's return . The team consists of Lucas , Melissa , Jenna , Sydney , and various other people that were treated badly by Alison . In the season five mid season finale , she is killed by Big `` A '' after acquiring information that proves Alison is Big `` A '' . In the second half of the season , it is revealed that Mona never thought Alison was Big `` A '' and instead , it was a plot by her and Big `` A '' to get Alison into jail . Mona was to fake her death as part of this plan , so that she could find out Big `` A 's '' identity , and in the fifth - season finale it was revealed that Mona is really alive and being forced to `` be '' Alison inside Big `` A '' 's Dollhouse . She escapes the Dollhouse with the other girls in season six , and ends up finding out Big `` A 's '' true identity to be CeCe Drake , alongside the others . During this revelation , Mona realizes that she was the one who hit Bethany Young with a shovel that night , believing she hit Alison , but discovering the truth once CeCe reveals that it was her who hit Alison . </P>
who plays the character a in pretty little liars
who plays the character a in pretty little liars
Janel Parrish
Janel Parrish