Sian O'Callaghan, 22, disappeared after leaving Swindon's Suju nightclub in the early hours of March 19 last year after a night out with friends.
Hundreds of volunteers turned out at Savernake Forest to help in the search for her but police found her body in Uffington, Oxfordshire, on March 24 after being taken there by Halliwell.
Miss O'Callaghan left the nightclub at 2.53am for the short walk to the home she shared with boyfriend Kevin Reape.
Shortly after she walked past the Goddard Arms on the High Street in the Old Town area, she fell into Halliwell's clutches by getting into his taxi.
What is moral is not always legal. That's the hard and uncomfortable lesson of the investigation into the disappearance of Sian O'Callaghan.
Christopher Halliwell to serve 30 years for the murder of Sian O'Callaghan. But escapes justice over second murder after police blunder.