The Bradford Bulls' full-back and goal-kicker will line up at Huddersfield this afternoon, intent on blocking the way to Wembley for the regime that gave him his chance and then promptly discarded him a few months ago.
It has been a remarkable year for Cook, who is still only 19. At first, the arrival of Dean Bell and Hugh McGahan as Leeds' new management team seemed to have given him the opportunity he craved.
He was promoted to the first team ahead of more seasoned players, and performed so well that he was added to England's squad for the World Cup. No sooner was the ink dry on that entry in his CV, however, than Leeds had packed him off to Bradford in exchange for Carl Hall - a deal that caused some amazement both inside and outside Headingley.
"It came right out of the blue and I couldn't quite believe it at the time," he said. "There's still a bit of shock there but, on the other hand, I'm grateful to Dean and Hugh for giving me my chance. If it wasn't for the start they gave me, I wouldn't be anywhere near a Challenge Cup semi-final at this stage in my career."
Cook still lives in Leeds and spends most evenings practising the skill that could bring his old club down on enemy territory. "I like to practice kicking for an hour a day, if not at the club then out on a field in Leeds with my brother."
Important as his marksmanship could be in what promises to be a close match, it is Cook's all-round game that will be watched with the most interest as he develops over the next few years. The word from Headingley after the surprise of his departure was that the coaching staff had identified flaws in his technique, especially in defence.
If there is any truth in that assessment, Bradford's coaching staff believe they can straighten him out, through the medium of one-to-one technical sessions that were not part of the routine at Leeds.
"They think nothing here of spending a couple of hours working on your game individually with you," he says. "On top of that, the team spirit here is like nothing I've ever known."
If proving that they were wrong to let him go gives Cook one good reason to shine against Leeds, then his personal Wembley history provides another. "I've been there four times - twice with Leeds and twice with England - each time as travelling reserve," he said. "It has been frustrating to go there and not get on to the field and this is my chance to put that right."
Bradford, as so often, have other former Leeds players in their squad. Paul Medley arrived, via Halifax, almost seven years ago, while Jon Scales made the short journey from Headingley last summer. Their coach, Brian Smith, might be happier if he could play another ex-Leeds man, the Cup-tied hooker, James Lowes, this afternoon, as well as another recent acquisition, Glen Tomlinson.
Even without them, there is an atmosphere of confidence at Odsal. Smith admits, however: "They beat us three times last season and have been to Wembley for the last two years. They have to be regarded as favourites."
Leeds have lost rather too many important players from their side to look entirely convincing. With Lowes, Craig Innes and Garry Schofield all departed and Tony Kemp injured, they are threadbare in some departments.
George Mann can be surprisingly effective at stand-off, however, and if Kevin Iro is in the mood Bradford will be hard-pressed to stop them making it three Wembley visits in three years.
Clive Griffiths, the Wales coach and former assistant at Warrington, has been named as coach of the new club in south Wales. Mike Nicholas, the former Wales and Warrington forward who has set up the new club and plans to announce his playing squad soon, said that Griffiths had always been the first choice for the job.
An Australian court has granted a temporary injunction to stop Maurice Lindsay and the players so far signed to Super League setting up a competition of their own under the Global League banner. The full bench of the court will consider the matter further on Monday.Reuse content