11 December 2005.
The emerging teenager looked as if he was set for greatness and was whisked off to Arsenal before he could hit the net again. Things didn't all work out for him there - historic highs and heart-wrenching lows came in equal measure throughout his 12 years at the Emirates, before he left for Everton, where he struggled to deliver on his £20m price tag.
His long, winding path brought him back to where it all started in October. And Southampton will be praising the heavens that it did.
The 31-year-old has provided Ralph Hasenhuttl with a creative solution to the problem posed by Danny Ings' latest injury. He will never be as prolific as the striker who has scored 30 goals since the beginning of last season, but what he can match is Ings' energy and enthusiasm on the front lines.
That was evident against Newcastle a week ago, when he joined Che Adams in a promising-looking partnership and set up the 24-year-old's opening goal.
The same combination crafted the opener at Molineux on Monday, but this time it was Walcott who was placed to coolly convert at the back post.
The finish was simple but it was indicative of the performances he has turned in since Hasenhuttl opted to move him inside. Nelson Semedo's defending was awful, but Walcott read it and positioned himself as if he had been playing centre-forward all his life.
He seems to be thriving in his new position, relishing the prospect of running at centre-backs and catching defences off-guard with his early runs. He perhaps should have doubled the lead after a long ball from Adams left him with all the time in the world, but he lost his composure when faced up by Rui Patricio one on one.
Speaking to reporters after the match, he reminded us what Theo Walcott looked like with a smile on his face. Rejuvenated, radiating charm, and oozing a child-like enthusiasm at the prospect of playing football regularly yet again.
When he was stuck in Goodison Park purgatory, you'd have forgiven for thinking that we'd seen the last of the player who was once English football's great white hope. Thanks to a trusting manager and a team that values him, however, it's beginning to seem like there is far more to come.