Murder and mystery surround BBC Three this week as a group of family and friends travel to a secluded island to attend a wedding. On Harper’s Island they’ve come to laugh, love and, although they don’t know it, die.

As the wedding festivities begin, friendships are tested and secrets are exposed as a murderer claims victims one by one – transforming the wedding week of fun and celebration into a terrifying struggle for survival.

Henry, the boy next door, is marrying the woman of his dreams, Trish Wellington – a beautiful and wealthy heiress. However, as the week begins, people start dying. Wedding guests and island locals are all suspects and nobody is safe.

In tonight’s opener, Abby Mills returns to Harper’s Island for her best friend, Henry’s, wedding. However, she hasn’t been home in seven years and is still haunted by the death of her mother and five others, who were murdered by John Wakefield on Harper’s Island…

Henry Dunn is played by Christopher Gorham, Trish Wellington by Katie Cassidy and Abby Mills by Elaine Cassidy. Harper’s Island also stars: Cameron Richardson as Chloe Carter; Adam Campbell as Cal Vandeusen; CJ Thomson as Jimmy Mance; Jim Beaver as Sheriff Charlie Mill; Matt Barr as Christopher “Sully” Sullivan; Amber Borycki as Beth Barrington; Richard Burgi as Thomas Wellington; Dean Chekvala as JD Dunn; and Ben Cotton as Shane Pierce.

Sunday 6 September
9.00-9.40pm BBC THREE