Is Pretty Little Liars coming back?

In Amerta University, 5 girls form the most popular clique in school – Aria, Hanna, Sabrina, Ema, and Alissa. One night, the best friends party at Sabrina's pool house. But when they wake up, they discover Alissa is missing. These 4 girls are forced back into one another's lives when they receive messages blackmailing them with secrets only Alissa could have known. The messages come from someone who calls themselves ‘A'. The old gang bands together as they become convinced that ‘A' must be Alissa, who is out there somewhere taunting them. That is, until Alissa's body is discovered in the backyard of her villa. So who killed Alissa? And if Alissa is dead... then who is ‘A'?