The six-year-old gelding - bred and previously owned by Zara Tindall - thrived in first-time blinkers to take the three-runner Watch Racing UK Anywhere Chase by three and a half lengths.
Keighley's inmate only had odds-on favourite Bentelimar to worry about once Justforjames wilted out of contention.
But Somewhere To Be always looked in control under Aidan Coleman and galloped through the heavy ground to collect quite comfortably.
Keighley said of the 6-4 chance: "The blinkers did their job and it was a good performance.
"It was also good prize-money for a three-runner race so we're really happy.
"There was a slight concern about the ground. He probably didn't enjoy it, but he did cope with it.
"He's only a young horse and there's probably quite a lot of improvement still to come from him."
Phil Kirby was similarly effusive in his appraisal of Sakhee's City (11-2) after he convincingly won the extended two-mile-three-furlong handicap hurdle by seven lengths.
Zeroeshadesofgrey did most of the hard work up front until the Kirby runner made his move before the final flight.
It was then all over as a contest as Sakhee's City stayed on in good style for Adam Nicol.
Kirby said: "To be fair, she's got loads of ability but she just needs things to drop right for her.
"She also likes it at Catterick, which is maybe unusual as a big horse like her might be better suited to a more galloping track.
"If there's something for her at Catterick, we might go back there again, but it's more likely that she'll go chasing sooner rather than later.
"She's schooled well over fences and has been entered up already, so that's the route we'll probably take with her."
Totalize (11-4) later made light work of a long absence to win the two-mile novice chase for the Brian Ellison team.
Kelka looks a nice recruit to the chasing game, but connections of the short-priced market leader had not counted upon Ellison having his nine-year-old so sharp after a 543-day break.
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