The Hatters were beaten by a West Brom side playing their first home game since being relegated from the Premier League this afternoon, but didn't go down without a fight having been 3-0 down with 20 minutes to go.
Albion controlled the game from the start and led through an early Kal Naismith own goal, and further strikes from Callum Robinson and Karlan Grant.
But the Hatters, who saw Jordan Clark carried off on a stretcher after suffering a serious blow to the head early in the second half, made the Baggies sweat with goals from Harry Cornick and Pelly-Ruddock Mpanzu, on his 300th appearance for the club, making the scoreline respectable in a game that ended with 16 minutes of added time.
Manager Nathan Jones named an unchanged team to the one that beat Peterborough 3-0 at home in the season opener, with the only change being on the bench where Dion Pereira replaced Glen Rea, who was unwell on the morning of the game.
Albion had the game's first attempt on goal in the opening minute, Callum Robinson 20-yard curler clearing Simon Sluga's crossbar, but it wasn't long before they had the lead - Darnell Furlong's long throw from the right headed past his own keeper by captain Kal Naismith in the fifth minute.
Backed by a raucous home crowd and buoyed by the goal, the Baggies were well on top on the early stages, Grady Diangana trying his luck from distance and Karlan Grant's shot from a short corner routine blocked, with Allan Campbell becoming the first player to see yellow for a late challenge in between.
Sluga was equal to another Grant drive on 25 minutes, Furlong firing the rebound over, before Albion's summer signing from Barnsley, Alex Mowatt, went into ref Tim Robinson's book for a foul that halted Fred Onyedinma's progress down the left.
The Hatters' Croatian keeper was on his mettle again soon after the half-hour, turning a Matt Clarke header from another Furlong throw over his bar, then denying the on-loan Brighton centre-half's near-post flick with Naismith managing to divert a header from Robinson wide in between.
There was no denying Robinson from that resulting corner though, the former Sheffield United striker nodding home at the far post from another set piece routine on 36 minutes.
Gabe Osho made a timely intervention to prevent Grant sliding a ball into the path of Robinson, as the clock ticked towards the end of a half dominated from start to finish by the hosts.
Jones made a change at the break, bringing Henri Lansbury into midfield and taking Onyedinma off. He was soon having to make a second switch, with Clark suffering a heavy blow to the heas when he went bravely into a challenge with England keeper Sam Johnstone.
The game was held up for 11 minutes as the Town attacker was treated on the pitch, before being carried off on a stretcher to applause from all four sides of The Hawthorns, Admiral Muskwe coming on in his place.
It was 3-0 in the 66th minute when Robinson drove into the Town box and set Grant up for an emphatic volley past Sluga.
Town grabbed a goal back four minutes later when Campbell charged down Conor Townsend's attempted clearance, and the ball ricocheted across the six-yard box for Cornick to slot in his second goal of the season.
Osho was booked for pulling Townsend back in the 74th minute, substitute Matt Phillips rattling the woodwork with the resulting free-kick, with Jones replacing Campbell with Peter Kioso.
He made a fourth substitution, bringing Cameron Jerome on in the 88th minute for Adebayo, and within seconds the Town had created a chance for Amari'i Bell to square across the box for Muskwe, but his attempt was deflected behind.
Then, with 16 minutes of added time just announced, Bree crossed low for the former Leicester man to steer another shot on target, only for Johnstone to repel his effort.
The Hatters were now having a real go, and after Johnstone had come out of his box to win a race to the ball with Jerome, Cornick's attempt to send it back over his head was wayward, and Bell couldn't direct his shot on target after doing well to retrieve possession.
A Cornick long throw led to concern in the hosts' box, with Mpanzu calling Johnstone into action in the 97th minute - seconds before the longest serving player marked his 300th appearance with as simple a goal as he's ever scored, after Cornick's initial shot was blocked.
Albion - Naismith (OG) 5, Robinson 36, Grant 66
Town - Cornick 70, Mpanzu 90+8