Starring on and off-screen couple Robert Pattinson and Kristen Stewart, and actor Taylor Lautner, the clip gives a much-anticipated look at what's in store for Bella Swan, vampire Edward Cullen and his werewolf love rival, Jacob Black.
It comes hot on the heels of a 10-second snippet released 24 hours beforehand, and gives viewers their very first look at newcomer Bryce Dallas Howard, who has replaced Rachelle Lefevre as flame-haired vampire, Victoria.
Sixteen-year-old Dakota Fanning – who recently teamed up with Kristen in The Runaways - also makes an appearance in her recurring role as Volturi guard Jane.
Eclipse is scheduled for release on June 30 and sees Bella struggle to chose between her love for Edward and her friendship with Jacob.
Hunted by vampire Victoria seeking revenge for the death of her lover James, the brunette student also faces a much harder decision – choosing between mortality and immortality.