who were the actors?
Ed Westwick, Leighton Meester and Michael Boatman.
The Wrong Goodbye (Gossip Girl)
"The Wrong Goodbye" picks up where the previous episode had left off. Chuck Bass (Ed Westwick) looks for a missing Blair Waldorf (Leighton Meester) who has been held hostage by an unstable Russell Thorpe (Michael Boatman). 
what is 'the wrong goodbye (gossip girl)'? It is the 87th episode of the television series "Gossip Girl". what is it about? It picks up where the previous episode had left off. Chuck Bass looks for a missing Blair Waldorf, who has been held hostage by an unstable Russell Thorpe.
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The Wrong Goodbye (Gossip Girl) [SEP] Introduction
Chuck Bass (Ed Westwick) looks for a missing Blair Waldorf (Leighton Meester) who has been held hostage by an unstable Russell Thorpe (Michael Boatman). An erratic Charlie Rhodes (Kaylee DeFer) escapes the humiliation of being rejected by Dan Humphrey (Penn Badgley). Serena van der Woodsen (Blake Lively) and Vanessa Abrams (Jessica Szohr) reluctantly join forces after discovering the secret behind Charlie's behavior. Georgina Sparks (Michelle Trachtenberg) unexpectedly turns up at the event looking for trouble. Jessica Szohr makes her final appearance as Vanessa Abrams; her exit was noted as her highlight of season 4, with many critics praising Szhor's acting in her phone conversation with Dan.