Arrow is an American television series developed by writer/producers Greg Berlanti, Marc Guggenheim, and Andrew Kreisberg. It is based on the DC Comics character Green Arrow, a costumed crime-fighter who was created by Mort Weisinger and George Papp. It premiered in North America on The CW on October 10, 2012, with international broadcasting taking place in late 2012. The series follows billionaire playboy Oliver Queen, portrayed by Stephen Amell, who, after five years of being stranded on a hostile island, returns home to fight crime and corruption as a secret vigilante whose weapon of choice is a bow and arrow. Unlike in the comic books, Oliver does not go by the alias "Green Arrow" in the television series. Arrow also features appearances by other DC Comics characters.
The show stepped up mid-way through season 1 and became really good from the beginning of season 2. It's even getting its own Flash spin-off show after Barry Allen was introduced in season 2. Spoiler box anything which hasn't aired on Sky yet.
Yes Green Arrow murders more people in season 1 than Dr Lecter did in season 1 of Hannibal but you get used to it.